Aracılığıyla paylaş


AccessibleObject Sınıf

Tanım

Erişilebilirlik uygulamalarının, engelli kullanıcılar için uygulamanın kullanıcı arabirimini (UI) ayarlamak için kullandığı bilgileri sağlar.

public ref class AccessibleObject : MarshalByRefObject, Accessibility::IAccessible, System::Reflection::IReflect
public ref class AccessibleObject : System::Runtime::InteropServices::StandardOleMarshalObject, Accessibility::IAccessible, System::Reflection::IReflect
[System.Runtime.InteropServices.ComVisible(true)]
public class AccessibleObject : MarshalByRefObject, Accessibility.IAccessible, System.Reflection.IReflect
[System.Runtime.InteropServices.ComVisible(true)]
public class AccessibleObject : System.Runtime.InteropServices.StandardOleMarshalObject, Accessibility.IAccessible, System.Reflection.IReflect
public class AccessibleObject : System.Runtime.InteropServices.StandardOleMarshalObject, Accessibility.IAccessible, System.Reflection.IReflect
[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
    inherit MarshalByRefObject
    interface IReflect
    interface IAccessible
    interface UnsafeNativeMethods.IEnumVariant
    interface UnsafeNativeMethods.IMarshal
[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
    inherit StandardOleMarshalObject
    interface IReflect
    interface IAccessible
    interface UnsafeNativeMethods.IEnumVariant
    interface UnsafeNativeMethods.IOleWindow
[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
    inherit StandardOleMarshalObject
    interface IReflect
    interface IAccessible
[<System.Runtime.InteropServices.ComVisible(true)>]
type AccessibleObject = class
    inherit StandardOleMarshalObject
    interface IReflect
    interface IAccessible
    interface UnsafeNativeMethods.IAccessibleEx
    interface UnsafeNativeMethods.IServiceProvider
    interface UnsafeNativeMethods.IRawElementProviderSimple
    interface UnsafeNativeMethods.IRawElementProviderFragment
    interface UnsafeNativeMethods.IRawElementProviderFragmentRoot
    interface UnsafeNativeMethods.IInvokeProvider
    interface UnsafeNativeMethods.IValueProvider
    interface UnsafeNativeMethods.IRangeValueProvider
    interface UnsafeNativeMethods.IExpandCollapseProvider
    interface UnsafeNativeMethods.IToggleProvider
    interface UnsafeNativeMethods.ITableProvider
    interface UnsafeNativeMethods.ITableItemProvider
    interface UnsafeNativeMethods.IGridProvider
    interface UnsafeNativeMethods.IGridItemProvider
    interface UnsafeNativeMethods.IEnumVariant
    interface UnsafeNativeMethods.IOleWindow
    interface UnsafeNativeMethods.ILegacyIAccessibleProvider
    interface UnsafeNativeMethods.ISelectionProvider
    interface UnsafeNativeMethods.ISelectionItemProvider
    interface UnsafeNativeMethods.IRawElementProviderHwndOverride
    interface UnsafeNativeMethods.IScrollItemProvider
type AccessibleObject = class
    inherit StandardOleMarshalObject
    interface IReflect
    interface IAccessible
    interface Interop.UiaCore.IAccessibleEx
    interface Interop.Ole32.IServiceProvider
    interface Interop.UiaCore.IRawElementProviderSimple
    interface Interop.UiaCore.IRawElementProviderFragment
    interface Interop.UiaCore.IRawElementProviderFragmentRoot
    interface Interop.UiaCore.IInvokeProvider
    interface Interop.UiaCore.IValueProvider
    interface Interop.UiaCore.IRangeValueProvider
    interface Interop.UiaCore.IExpandCollapseProvider
    interface Interop.UiaCore.IToggleProvider
    interface Interop.UiaCore.ITableProvider
    interface Interop.UiaCore.ITableItemProvider
    interface Interop.UiaCore.IGridProvider
    interface Interop.UiaCore.IGridItemProvider
    interface Interop.Oleaut32.IEnumVariant
    interface Interop.Ole32.IOleWindow
    interface Interop.UiaCore.ILegacyIAccessibleProvider
    interface Interop.UiaCore.ISelectionProvider
    interface Interop.UiaCore.ISelectionItemProvider
    interface Interop.UiaCore.IRawElementProviderHwndOverride
    interface Interop.UiaCore.IScrollItemProvider
    interface Interop.UiaCore.IMultipleViewProvider
    interface Interop.UiaCore.ITextProvider
    interface Interop.UiaCore.ITextProvider2
Public Class AccessibleObject
Inherits MarshalByRefObject
Implements IAccessible, IReflect
Public Class AccessibleObject
Inherits StandardOleMarshalObject
Implements IAccessible, IReflect
Devralma
AccessibleObject
Devralma
Türetilmiş
Öznitelikler
Uygulamalar

Örnekler

Aşağıdaki kod örneği, erişilebilir bilgileri kullanıma açmak için ve Control.ControlAccessibleObject sınıflarını kullanarak erişilebilirliği algılayan bir grafik denetiminin oluşturulmasını AccessibleObject gösterir. Denetim, bir göstergeyle birlikte iki eğri çizer. ChartControlAccessibleObject sınıfından ControlAccessibleObjecttüretilen sınıfı, grafik denetimi için özel erişilebilir bilgiler sağlamak için yönteminde CreateAccessibilityInstance kullanılır. Grafik göstergesi gerçek Control tabanlı bir denetim olmadığından, bunun yerine grafik denetimi tarafından çizildiğinden, herhangi bir yerleşik erişilebilir bilgiye sahip değildir. Bu nedenle sınıfı, göstergenin ChartControlAccessibleObject GetChild her parçası için erişilebilir bilgileri temsil eden öğesini döndürmek CurveLegendAccessibleObject için yöntemini geçersiz kılar. Erişilebilirliğe duyarlı bir uygulama bu denetimi kullandığında, denetim gerekli erişilebilir bilgileri sağlayabilir.

#using <Accessibility.dll>
#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;

// Declare a chart control that demonstrates accessibility in Windows Forms.
public ref class ChartControl: public System::Windows::Forms::UserControl
{
public:
   ref class ChartControlAccessibleObject;

   // forward declaration
   // Inner Class that represents a legend for a curve in the chart.
   ref class CurveLegend
   {

      // Inner class CurveLegendAccessibleObject represents accessible information
      // associated with the CurveLegend object.
   public:
      ref class CurveLegendAccessibleObject: public AccessibleObject
      {
      private:
         CurveLegend^ curveLegend;

      public:
         CurveLegendAccessibleObject( CurveLegend^ curveLegend )
            : AccessibleObject()
         {
            this->curveLegend = curveLegend;
         }


      private:

         property ChartControlAccessibleObject^ ChartControl 
         {

            // Private property that helps get the reference to the parent ChartControl.
            ChartControlAccessibleObject^ get()
            {
               return dynamic_cast<ChartControlAccessibleObject^>(Parent);
            }

         }

      internal:

         property int ID 
         {

            // Internal helper function that returns the ID for this CurveLegend.
            int get()
            {
               for ( int i = 0; i < ChartControl->GetChildCount(); i++ )
               {
                  if ( ChartControl->GetChild( i ) == this )
                  {
                     return i;
                  }

               }
               return  -1;
            }

         }

      public:

         property Rectangle Bounds 
         {

            // Gets the Bounds for the CurveLegend. This is used by accessibility programs.
            virtual Rectangle get() override
            {
               
               // The bounds is in screen coordinates.
               Point loc = curveLegend->Location;
               return Rectangle(curveLegend->chart->PointToScreen( loc ),curveLegend->Size);
            }

         }

         property String^ Name 
         {

            // Gets or sets the Name for the CurveLegend. This is used by accessibility programs.
            virtual String^ get() override
            {
               return curveLegend->Name;
            }

            virtual void set( String^ value ) override
            {
               curveLegend->Name = value;
            }

         }

         property AccessibleObject^ Parent 
         {

            // Gets the Curve Legend Parent's Accessible object.
            // This is used by accessibility programs.
            virtual AccessibleObject^ get() override
            {
               return curveLegend->chart->AccessibilityObject;
            }

         }

         property System::Windows::Forms::AccessibleRole Role 
         {

            // Gets the role for the CurveLegend. This is used by accessibility programs.
            virtual System::Windows::Forms::AccessibleRole get() override
            {
               return ::AccessibleRole::StaticText;
            }

         }

         property AccessibleStates State 
         {

            // Gets the state based on the selection for the CurveLegend.
            // This is used by accessibility programs.
            virtual AccessibleStates get() override
            {
               AccessibleStates state = AccessibleStates::Selectable;
               if ( curveLegend->Selected )
               {
                  state = static_cast<AccessibleStates>(state | AccessibleStates::Selected);
               }

               return state;
            }

         }

         // Navigates through siblings of this CurveLegend. This is used by accessibility programs.
         virtual AccessibleObject^ Navigate( AccessibleNavigation navdir ) override
         {
            
            // Uses the internal NavigateFromChild helper function that exists
            // on ChartControlAccessibleObject.
            return ChartControl->NavigateFromChild( this, navdir );
         }


         // Selects or unselects this CurveLegend. This is used by accessibility programs.
         virtual void Select( AccessibleSelection selection ) override
         {
            
            // Uses the internal SelectChild helper function that exists
            // on ChartControlAccessibleObject.
            ChartControl->SelectChild( this, selection );
         }

      };


   private:

      // class CurveLgendAccessibleObject
      String^ name;
      ChartControl^ chart;
      CurveLegendAccessibleObject^ accObj;
      bool selected;
      Point location;

   public:
      CurveLegend( ChartControl^ chart, String^ name )
      {
         this->chart = chart;
         this->name = name;
         selected = true;
      }


      property AccessibleObject^ AccessibilityObject 
      {

         // Gets the accessibility object for the curve legend.
         AccessibleObject^ get()
         {
            if ( accObj == nullptr )
            {
               accObj = gcnew CurveLegendAccessibleObject( this );
            }

            return accObj;
         }

      }

      property Rectangle Bounds 
      {

         // Gets the bounds for the curve legend.
         Rectangle get()
         {
            return Rectangle(Location,Size);
         }

      }

      property Point Location 
      {

         // Gets or sets the location for the curve legend.
         Point get()
         {
            return location;
         }

         void set( Point value )
         {
            location = value;
            chart->Invalidate();
            
            // Notifies the chart of the location change. This is used for
            // the accessibility information. AccessibleEvents::LocationChange
            // tells the chart the reason for the notification.
            chart->AccessibilityNotifyClients( AccessibleEvents::LocationChange, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
         }

      }

      property String^ Name 
      {

         // Gets or sets the Name for the curve legend.
         String^ get()
         {
            return name;
         }

         void set( String^ value )
         {
            if ( name != value )
            {
               name = value;
               chart->Invalidate();
               
               // Notifies the chart of the name change. This is used for
               // the accessibility information. AccessibleEvents::NameChange
               // tells the chart the reason for the notification.
               chart->AccessibilityNotifyClients( AccessibleEvents::NameChange, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
            }
         }

      }

      property bool Selected 
      {

         // Gets or sets the Selected state for the curve legend.
         bool get()
         {
            return selected;
         }

         void set( bool value )
         {
            if ( selected != value )
            {
               selected = value;
               chart->Invalidate();
               
               // Notifies the chart of the selection value change. This is used for
               // the accessibility information. The AccessibleEvents value depends upon
               // if the selection is true (AccessibleEvents::SelectionAdd) or
               // false (AccessibleEvents::SelectionRemove).
               chart->AccessibilityNotifyClients( selected ? AccessibleEvents::SelectionAdd : AccessibleEvents::SelectionRemove, (dynamic_cast<CurveLegendAccessibleObject^>(AccessibilityObject))->ID );
            }
         }

      }

      property System::Drawing::Size Size 
      {

         // Gets the Size for the curve legend.
         System::Drawing::Size get()
         {
            int legendHeight = chart->Font->Height + 4;
            Graphics^ g = chart->CreateGraphics();
            int legendWidth = (int)g->MeasureString( Name, chart->Font ).Width + 4;
            return System::Drawing::Size( legendWidth, legendHeight );
         }

      }

   };


private:

   // class CurveLegend
   CurveLegend^ legend1;
   CurveLegend^ legend2;

public:
   ChartControl()
   {
      
      // The ChartControl draws the chart in the OnPaint .
      SetStyle( ControlStyles::ResizeRedraw, true );
      SetStyle( ControlStyles::DoubleBuffer, true );
      SetStyle( ControlStyles::AllPaintingInWmPaint, true );
      this->BackColor = System::Drawing::Color::White;
      this->Name = "ChartControl";
      this->Click += gcnew System::EventHandler( this, &ChartControl::ChartControl_Click );
      this->QueryAccessibilityHelp += gcnew System::Windows::Forms::QueryAccessibilityHelpEventHandler( this, &ChartControl::ChartControl_QueryAccessibilityHelp );
      
      // The CurveLengend is not Control-based, it just
      // represents the parts of the legend.
      legend1 = gcnew CurveLegend( this,"A" );
      legend1->Location = Point(20,30);
      legend2 = gcnew CurveLegend( this,"B" );
      legend2->Location = Point(20,50);
   }



protected:
   // Overridden to return the custom AccessibleObject
   // for the entire chart.
   virtual AccessibleObject^ CreateAccessibilityInstance() override
   {
      return gcnew ChartControlAccessibleObject( this );
   }

   virtual void OnPaint( PaintEventArgs^ e ) override
   {
      
      // The ChartControl draws the chart in the OnPaint .
      System::Windows::Forms::UserControl::OnPaint( e );
      Rectangle bounds = this->ClientRectangle;
      int border = 5;
      
      // Draws the legends first.
      StringFormat^ format = gcnew StringFormat;
      format->Alignment = StringAlignment::Center;
      format->LineAlignment = StringAlignment::Center;
      if ( legend1 != nullptr )
      {
         if ( legend1->Selected )
         {
            e->Graphics->FillRectangle( gcnew SolidBrush( Color::Blue ), legend1->Bounds );
         }
         else
         {
            e->Graphics->DrawRectangle( Pens::Blue, legend1->Bounds );
         }

         e->Graphics->DrawString( legend1->Name, this->Font, Brushes::Black, legend1->Bounds, format );
      }

      if ( legend2 != nullptr )
      {
         if ( legend2->Selected )
         {
            e->Graphics->FillRectangle( gcnew SolidBrush( Color::Red ), legend2->Bounds );
         }
         else
         {
            e->Graphics->DrawRectangle( Pens::Red, legend2->Bounds );
         }

         e->Graphics->DrawString( legend2->Name, this->Font, Brushes::Black, legend2->Bounds, format );
      }

      
      // Charts out the actual curves that represent data in the Chart.
      bounds.Inflate(  -border,  -border );
      array<Point>^ temp1 = {Point(bounds.Left,bounds.Bottom),Point(bounds.Left + bounds.Width / 3,bounds.Top + bounds.Height / 5),Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2),Point(bounds.Right,bounds.Top)};
      array<Point>^curve1 = temp1;
      array<Point>^ temp2 = {Point(bounds.Left,bounds.Bottom - bounds.Height / 3),Point(bounds.Left + bounds.Width / 3,bounds.Top + bounds.Height / 5),Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2),Point(bounds.Right,bounds.Top + bounds.Height / 2)};
      array<Point>^curve2 = temp2;
      
      // Draws the actual curve only if it is selected.
      if ( legend1->Selected )
            e->Graphics->DrawCurve( Pens::Blue, curve1 );

      if ( legend2->Selected )
            e->Graphics->DrawCurve( Pens::Red, curve2 );

      e->Graphics->DrawRectangle( Pens::Blue, bounds );
   }

   // Handles the QueryAccessibilityHelp event.
   void ChartControl_QueryAccessibilityHelp( Object^ /*sender*/, System::Windows::Forms::QueryAccessibilityHelpEventArgs^ e )
   {
      e->HelpString = "Displays chart data";
   }

   // Handles the Click event for the chart.
   // Toggles the selection of whatever legend was clicked on
   void ChartControl_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      Point pt = this->PointToClient( Control::MousePosition );
      if ( legend1->Bounds.Contains( pt ) )
      {
         legend1->Selected =  !legend1->Selected;
      }
      else
      if ( legend2->Bounds.Contains( pt ) )
      {
         legend2->Selected =  !legend2->Selected;
      }
   }


public:

   property array<CurveLegend^>^ Legends 
   {

      // Gets an array of CurveLengends used in the Chart.
      array<CurveLegend^>^ get()
      {
         array<CurveLegend^>^temp3 = {legend1,legend2};
         return temp3;
      }

   }

   // Inner class ChartControlAccessibleObject represents accessible information associated with the ChartControl.
   // The ChartControlAccessibleObject is returned in the ChartControl::CreateAccessibilityInstance .
   ref class ChartControlAccessibleObject: public ControlAccessibleObject
   {
   private:
      ChartControl^ chartControl;

   public:
      ChartControlAccessibleObject( ChartControl^ ctrl )
         : ControlAccessibleObject( ctrl )
      {
         chartControl = ctrl;
      }


      property System::Windows::Forms::AccessibleRole Role 
      {

         // Gets the role for the Chart. This is used by accessibility programs.
         virtual System::Windows::Forms::AccessibleRole get() override
         {
            return ::AccessibleRole::Chart;
         }

      }

      property AccessibleStates State 
      {

         // Gets the state for the Chart. This is used by accessibility programs.
         virtual AccessibleStates get() override
         {
            return AccessibleStates::ReadOnly;
         }

      }

      // The CurveLegend objects are "child" controls in terms of accessibility so
      // return the number of ChartLengend objects.
      virtual int GetChildCount() override
      {
         return chartControl->Legends->Length;
      }


      // Gets the Accessibility object of the child CurveLegend idetified by index.
      virtual AccessibleObject^ GetChild( int index ) override
      {
         if ( index >= 0 && index < chartControl->Legends->Length )
         {
            return chartControl->Legends[ index ]->AccessibilityObject;
         }

         return nullptr;
      }


   internal:

      // Helper function that is used by the CurveLegend's accessibility object
      // to navigate between sibiling controls. Specifically, this function is used in
      // the CurveLegend::CurveLegendAccessibleObject.Navigate function.
      AccessibleObject^ NavigateFromChild( CurveLegend::CurveLegendAccessibleObject^ child, AccessibleNavigation navdir )
      {
         switch ( navdir )
         {
            case AccessibleNavigation::Down:
            case AccessibleNavigation::Next:
               return GetChild( child->ID + 1 );

            case AccessibleNavigation::Up:
            case AccessibleNavigation::Previous:
               return GetChild( child->ID - 1 );
         }
         return nullptr;
      }


      // Helper function that is used by the CurveLegend's accessibility object
      // to select a specific CurveLegend control. Specifically, this function is used
      // in the CurveLegend::CurveLegendAccessibleObject.Select function.
      void SelectChild( CurveLegend::CurveLegendAccessibleObject^ child, AccessibleSelection selection )
      {
         int childID = child->ID;
         
         // Determine which selection action should occur, based on the
         // AccessibleSelection value.
         if ( (selection & AccessibleSelection::TakeSelection) != (AccessibleSelection)0 )
         {
            for ( int i = 0; i < chartControl->Legends->Length; i++ )
            {
               if ( i == childID )
               {
                  chartControl->Legends[ i ]->Selected = true;
               }
               else
               {
                  chartControl->Legends[ i ]->Selected = false;
               }

            }
            
            // AccessibleSelection->AddSelection means that the CurveLegend will be selected.
            if ( (selection & AccessibleSelection::AddSelection) != (AccessibleSelection)0 )
            {
               chartControl->Legends[ childID ]->Selected = true;
            }
            
            // AccessibleSelection->AddSelection means that the CurveLegend will be unselected.
            if ( (selection & AccessibleSelection::RemoveSelection) != (AccessibleSelection)0 )
            {
               chartControl->Legends[ childID ]->Selected = false;
            }
         }
      }

   };

   // class ChartControlAccessibleObject
};


// class ChartControl
public ref class Form1: public System::Windows::Forms::Form
{
private:

   // Test out the Chart Control.
   ChartControl^ chart1;

public:
   Form1()
   {
      
      // Create a chart control and add it to the form.
      this->chart1 = gcnew ChartControl;
      this->ClientSize = System::Drawing::Size( 920, 566 );
      this->chart1->Location = System::Drawing::Point( 47, 16 );
      this->chart1->Size = System::Drawing::Size( 600, 400 );
      this->Controls->Add( this->chart1 );
   }

};


// class Form1

[STAThread]
int main()
{
   Application::Run( gcnew Form1 );
}
using System;
using System.Drawing;
using System.Windows.Forms;

namespace ChartControl
{
    public class Form1 : System.Windows.Forms.Form
    {
        // Test out the Chart Control.
        private ChartControl chart1;

        [STAThread]
        static void Main() 
        {
            Application.Run(new Form1());
        }

        public Form1() {
            // Create a chart control and add it to the form.
            this.chart1 = new ChartControl();
            this.ClientSize = new System.Drawing.Size(920, 566);

            this.chart1.Location = new System.Drawing.Point(47, 16);
            this.chart1.Size = new System.Drawing.Size(600, 400);

            this.Controls.Add(this.chart1);
        }
    }

    // Declare a chart control that demonstrates accessibility in Windows Forms.
    public class ChartControl : System.Windows.Forms.UserControl
    {
        private CurveLegend legend1;
        private CurveLegend legend2; 

        public ChartControl()
        {
            // The ChartControl draws the chart in the OnPaint override.
            SetStyle(ControlStyles.ResizeRedraw, true);
            SetStyle(ControlStyles.DoubleBuffer, true);
            SetStyle(ControlStyles.AllPaintingInWmPaint, true);

            this.BackColor = System.Drawing.Color.White;
            this.Name = "ChartControl";

            this.Click += new System.EventHandler(this.ChartControl_Click);
            this.QueryAccessibilityHelp += 
                new System.Windows.Forms.QueryAccessibilityHelpEventHandler(
                                        this.ChartControl_QueryAccessibilityHelp);

            // The CurveLengend is not Control-based, it just
            // represents the parts of the legend.
            legend1 = new CurveLegend(this, "A");
            legend1.Location = new Point(20, 30);
            legend2 = new CurveLegend(this, "B");        
            legend2.Location = new Point(20, 50);
        }

        // Overridden to return the custom AccessibleObject 
        // for the entire chart.
        protected override AccessibleObject CreateAccessibilityInstance() 
        {            
            return new ChartControlAccessibleObject(this);
        }

        protected override void OnPaint(PaintEventArgs e) 
        {
            // The ChartControl draws the chart in the OnPaint override.
            base.OnPaint(e);

            Rectangle bounds = this.ClientRectangle;
            int border = 5;

            // Draws the legends first.
            StringFormat format = new StringFormat();
            format.Alignment = StringAlignment.Center;
            format.LineAlignment = StringAlignment.Center;
            
            if (legend1 != null) {
                if (legend1.Selected) {
                    e.Graphics.FillRectangle(new SolidBrush(Color.Blue), legend1.Bounds);
                } else {
                    e.Graphics.DrawRectangle(Pens.Blue, legend1.Bounds);
                }

                e.Graphics.DrawString(legend1.Name, this.Font, Brushes.Black, legend1.Bounds, format);                
            }
            if (legend2 != null) {
                if (legend2.Selected) {
                    e.Graphics.FillRectangle(new SolidBrush(Color.Red), legend2.Bounds);
                } else {
                    e.Graphics.DrawRectangle(Pens.Red, legend2.Bounds);
                }
                e.Graphics.DrawString(legend2.Name, this.Font, Brushes.Black, legend2.Bounds, format);
            }            

            // Charts out the actual curves that represent data in the Chart.
            bounds.Inflate(-border, -border);
            Point[] curve1 = new Point[] {new Point(bounds.Left, bounds.Bottom),
                            new Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5),
                            new Point(bounds.Right - bounds.Width / 3, (bounds.Top + bounds.Bottom) / 2),
                            new Point(bounds.Right, bounds.Top)};

            Point[] curve2 = new Point[] {new Point(bounds.Left, bounds.Bottom - bounds.Height / 3),
                            new Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5),
                            new Point(bounds.Right - bounds.Width / 3, (bounds.Top + bounds.Bottom) / 2),
                            new Point(bounds.Right, bounds.Top + bounds.Height / 2)};

            // Draws the actual curve only if it is selected.
            if (legend1.Selected) e.Graphics.DrawCurve(Pens.Blue, curve1);
            if (legend2.Selected) e.Graphics.DrawCurve(Pens.Red, curve2);

            e.Graphics.DrawRectangle(Pens.Blue, bounds);            
        }

        // Handles the QueryAccessibilityHelp event.
        private void ChartControl_QueryAccessibilityHelp(object sender, 
                                    System.Windows.Forms.QueryAccessibilityHelpEventArgs e)
        {            
            e.HelpString = "Displays chart data";
        }          

        // Handles the Click event for the chart. 
        // Toggles the selection of whatever legend was clicked on
        private void ChartControl_Click(object sender, System.EventArgs e)
        {
            Point pt = this.PointToClient(Control.MousePosition);
            if (legend1.Bounds.Contains(pt)) {
                legend1.Selected = !legend1.Selected;
            } else if (legend2.Bounds.Contains(pt)) {
                legend2.Selected = !legend2.Selected;
            }
        }

        // Gets an array of CurveLengends used in the Chart.
        public CurveLegend[] Legends
        {   
            get {                
                return new CurveLegend[] { legend1, legend2 };
            }            
        }                

        // Inner class ChartControlAccessibleObject represents accessible information associated with the ChartControl.
        // The ChartControlAccessibleObject is returned in the ChartControl.CreateAccessibilityInstance override.
        public class ChartControlAccessibleObject : ControlAccessibleObject
        {
            ChartControl chartControl;

            public ChartControlAccessibleObject(ChartControl ctrl) : base(ctrl) 
            {
                chartControl = ctrl;
            }

            // Gets the role for the Chart. This is used by accessibility programs.
            public override AccessibleRole Role
            {  
                get {
                    return AccessibleRole.Chart;
                }
            }

            // Gets the state for the Chart. This is used by accessibility programs.
            public override AccessibleStates State
            {  
                get {                    
                    return AccessibleStates.ReadOnly;
                }
            }

            // The CurveLegend objects are "child" controls in terms of accessibility so 
            // return the number of ChartLengend objects.
            public override int GetChildCount()
            {  
                return chartControl.Legends.Length;
            }

            // Gets the Accessibility object of the child CurveLegend idetified by index.
            public override AccessibleObject GetChild(int index)
            {  
                if (index >= 0 && index < chartControl.Legends.Length) {
                    return chartControl.Legends[index].AccessibilityObject;
                }                
                return null;
            }

            // Helper function that is used by the CurveLegend's accessibility object
            // to navigate between sibiling controls. Specifically, this function is used in
            // the CurveLegend.CurveLegendAccessibleObject.Navigate function.
            internal AccessibleObject NavigateFromChild(CurveLegend.CurveLegendAccessibleObject child, 
                                                        AccessibleNavigation navdir) 
            {  
                switch(navdir) {
                    case AccessibleNavigation.Down:
                    case AccessibleNavigation.Next:
                        return GetChild(child.ID + 1);
                        
                    case AccessibleNavigation.Up:
                    case AccessibleNavigation.Previous:
                        return GetChild(child.ID - 1);                        
                }
                return null;
            }

            // Helper function that is used by the CurveLegend's accessibility object
            // to select a specific CurveLegend control. Specifically, this function is used
            // in the CurveLegend.CurveLegendAccessibleObject.Select function.
            internal void SelectChild(CurveLegend.CurveLegendAccessibleObject child, AccessibleSelection selection) 
            {   
                int childID = child.ID;

                // Determine which selection action should occur, based on the
                // AccessibleSelection value.
                if ((selection & AccessibleSelection.TakeSelection) != 0) {
                    for(int i = 0; i < chartControl.Legends.Length; i++) {
                        if (i == childID) {
                            chartControl.Legends[i].Selected = true;                        
                        } else {
                            chartControl.Legends[i].Selected = false;
                        }
                    }

                    // AccessibleSelection.AddSelection means that the CurveLegend will be selected.
                    if ((selection & AccessibleSelection.AddSelection) != 0) {
                        chartControl.Legends[childID].Selected = true;                        
                    }

                    // AccessibleSelection.AddSelection means that the CurveLegend will be unselected.
                    if ((selection & AccessibleSelection.RemoveSelection) != 0) {
                        chartControl.Legends[childID].Selected = false;                        
                    }
                }            
            }
        }

        // Inner Class that represents a legend for a curve in the chart.
        public class CurveLegend 
        {
            private string name;
            private ChartControl chart;
            private CurveLegendAccessibleObject accObj;
            private bool selected = true;
            private Point location;

            public CurveLegend(ChartControl chart, string name) 
            {
                this.chart = chart;
                this.name = name;
            }

            // Gets the accessibility object for the curve legend.
            public AccessibleObject AccessibilityObject
            {
                get
                {
                    accObj ??= new CurveLegendAccessibleObject(this);
                    return accObj;
                }
            }
            
            // Gets the bounds for the curve legend.
            public Rectangle Bounds
            {   
                get
                {
                    return new Rectangle(Location, Size);
                }
            }

            // Gets or sets the location for the curve legend.
            public Point Location
            {   
                get {
                    return location;
                }
                set {
                    location = value;
                    chart.Invalidate();

                    // Notifies the chart of the location change. This is used for
                    // the accessibility information. AccessibleEvents.LocationChange
                    // tells the chart the reason for the notification.

                    chart.AccessibilityNotifyClients(AccessibleEvents.LocationChange, 
                        ((CurveLegendAccessibleObject)AccessibilityObject).ID);
                }
            }            
        
            // Gets or sets the Name for the curve legend.
            public string Name
            {   
                get {
                    return name;
                }
                set {
                    if (name != value) 
                    {
                        name = value;
                        chart.Invalidate();

                        // Notifies the chart of the name change. This is used for
                        // the accessibility information. AccessibleEvents.NameChange
                        // tells the chart the reason for the notification.

                        chart.AccessibilityNotifyClients(AccessibleEvents.NameChange, 
                            ((CurveLegendAccessibleObject)AccessibilityObject).ID);
                    }
                }
            }

            // Gets or sets the Selected state for the curve legend.
            public bool Selected
            {   
                get {
                    return selected;
                }
                set {
                    if (selected != value) 
                    {
                        selected = value;
                        chart.Invalidate();

                        // Notifies the chart of the selection value change. This is used for
                        // the accessibility information. The AccessibleEvents value depends upon
                        // if the selection is true (AccessibleEvents.SelectionAdd) or 
                        // false (AccessibleEvents.SelectionRemove).
                        chart.AccessibilityNotifyClients(
                            selected ? AccessibleEvents.SelectionAdd : AccessibleEvents.SelectionRemove, 
                            ((CurveLegendAccessibleObject)AccessibilityObject).ID);
                    }
                }
            }

            // Gets the Size for the curve legend.
            public Size Size
            {   
                get {                    
                    int legendHeight = chart.Font.Height + 4;
                    Graphics g = chart.CreateGraphics();
                    int legendWidth = (int)g.MeasureString(Name, chart.Font).Width + 4;            

                    return new Size(legendWidth, legendHeight);
                }
            }
    
            // Inner class CurveLegendAccessibleObject represents accessible information 
            // associated with the CurveLegend object.
            public class CurveLegendAccessibleObject : AccessibleObject
            {
                private CurveLegend curveLegend;

                public CurveLegendAccessibleObject(CurveLegend curveLegend) : base() 
                {
                    this.curveLegend = curveLegend;                    
                }                

                // Private property that helps get the reference to the parent ChartControl.
                private ChartControlAccessibleObject ChartControl
                {   
                    get {
                        return Parent as ChartControlAccessibleObject;
                    }
                }

                // Internal helper function that returns the ID for this CurveLegend.
                internal int ID
                {
                    get {
                        for(int i = 0; i < ChartControl.GetChildCount(); i++) {
                            if (ChartControl.GetChild(i) == this) {
                                return i;
                            }
                        }
                        return -1;
                    }
                }

                // Gets the Bounds for the CurveLegend. This is used by accessibility programs.
                public override Rectangle Bounds
                {
                    get {                        
                        // The bounds is in screen coordinates.
                        Point loc = curveLegend.Location;
                        return new Rectangle(curveLegend.chart.PointToScreen(loc), curveLegend.Size);
                    }
                }

                // Gets or sets the Name for the CurveLegend. This is used by accessibility programs.
                public override string Name
                {
                    get {
                        return curveLegend.Name;
                    }
                    set {
                        curveLegend.Name = value;                        
                    }
                }

                // Gets the Curve Legend Parent's Accessible object.
                // This is used by accessibility programs.
                public override AccessibleObject Parent
                {
                    get {
                        return curveLegend.chart.AccessibilityObject;
                    }
                }

                // Gets the role for the CurveLegend. This is used by accessibility programs.
                public override AccessibleRole Role 
                {
                    get {
                        return AccessibleRole.StaticText;
                    }
                }

                // Gets the state based on the selection for the CurveLegend. 
                // This is used by accessibility programs.
                public override AccessibleStates State 
                {
                    get {
                        AccessibleStates state = AccessibleStates.Selectable;
                        if (curveLegend.Selected) 
                        {
                            state |= AccessibleStates.Selected;
                        }
                        return state;
                    }
                }

                // Navigates through siblings of this CurveLegend. This is used by accessibility programs.
                public override AccessibleObject Navigate(AccessibleNavigation navdir) 
                {
                    // Uses the internal NavigateFromChild helper function that exists
                    // on ChartControlAccessibleObject.
                    return ChartControl.NavigateFromChild(this, navdir);
                }

                // Selects or unselects this CurveLegend. This is used by accessibility programs.
                public override void Select(AccessibleSelection selection) 
                {
                    // Uses the internal SelectChild helper function that exists
                    // on ChartControlAccessibleObject.
                    ChartControl.SelectChild(this, selection);
                }
            }
        }
    }
}
Option Explicit

Imports System.Drawing
Imports System.Windows.Forms

Namespace ChartControlNameSpace
    
    Public Class Form1 
        Inherits System.Windows.Forms.Form

        ' Test out the Chart Control.
        Private chart1 As ChartControl

        <System.STAThread()> _
        Public Shared Sub Main()
            System.Windows.Forms.Application.Run(New Form1())
        End Sub

        Public Sub New() 
            ' Create a chart control and add it to the form.
            Me.chart1 = New ChartControl()
            Me.ClientSize = New System.Drawing.Size(920, 566)

            Me.chart1.Location = New System.Drawing.Point(47, 16)
            Me.chart1.Size = New System.Drawing.Size(600, 400)

            Me.Controls.Add(Me.chart1)
        End Sub
    End Class

    ' Declares a chart control that demonstrates Accessibility in Windows Forms.
    Public Class ChartControl
        Inherits System.Windows.Forms.UserControl

        Private legend1 As CurveLegend
        Private legend2 As CurveLegend
        
        Public Sub New()
            ' The ChartControl draws the chart in the OnPaint override.
            SetStyle(ControlStyles.ResizeRedraw, True)
            SetStyle(ControlStyles.DoubleBuffer, True)
            SetStyle(ControlStyles.AllPaintingInWmPaint, True)
            
            Me.BackColor = System.Drawing.Color.White
            Me.Name = "ChartControl"

            ' The CurveLengend is not Control-based, it just
            ' represent the parts of the legend.
            legend1 = New CurveLegend(Me, "A")
            legend1.Location = New Point(20, 30)
            legend2 = New CurveLegend(Me, "B")
            legend2.Location = New Point(20, 50)
        End Sub
              
        ' Overridden to return the custom AccessibleObject 
        ' for the entire chart.
        Protected Overrides Function CreateAccessibilityInstance() As AccessibleObject
            Return New ChartControlAccessibleObject(Me)
        End Function 

        Protected Overrides Sub OnPaint(e As PaintEventArgs)
            ' The ChartControl draws the chart in the OnPaint override.
            MyBase.OnPaint(e)
            
            Dim bounds As Rectangle = Me.ClientRectangle
            Dim border As Integer = 5
            
            ' Draw the legends first.
            Dim format As New StringFormat()
            format.Alignment = StringAlignment.Center
            format.LineAlignment = StringAlignment.Center
            
            If (legend1 IsNot Nothing) Then
                If legend1.Selected Then
                    e.Graphics.FillRectangle(New SolidBrush(Color.Blue), legend1.Bounds)
                Else
                    e.Graphics.DrawRectangle(Pens.Blue, legend1.Bounds)
                End If
                e.Graphics.DrawString(legend1.Name, Me.Font, Brushes.Black, RectangleF.op_Implicit(legend1.Bounds), format)
            End If
            If (legend2 IsNot Nothing) Then
                If legend2.Selected Then
                    e.Graphics.FillRectangle(New SolidBrush(Color.Red), legend2.Bounds)
                Else
                    e.Graphics.DrawRectangle(Pens.Red, legend2.Bounds)
                End If
                e.Graphics.DrawString(legend2.Name, Me.Font, Brushes.Black, RectangleF.op_Implicit(legend2.Bounds), format)
            End If
            
            ' Chart out the actual curves that represent data in the Chart.
            bounds.Inflate(-border, -border)
            Dim curve1() As Point = {New Point(bounds.Left, bounds.Bottom), _
                                     New Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5), _
                                     New Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2), _
                                     New Point(bounds.Right, bounds.Top)}

            Dim curve2() As Point = {New Point(bounds.Left, bounds.Bottom - bounds.Height / 3), _
                                     New Point(bounds.Left + bounds.Width / 3, bounds.Top + bounds.Height / 5), _
                                     New Point(bounds.Right - bounds.Width / 3,(bounds.Top + bounds.Bottom) / 2), _
                                     New Point(bounds.Right, bounds.Top + bounds.Height / 2)}
            
            ' Draw the actual curve only if it is selected.
            If legend1.Selected Then
                e.Graphics.DrawCurve(Pens.Blue, curve1)
            End If
            If legend2.Selected Then
                e.Graphics.DrawCurve(Pens.Red, curve2)
            End If 
            e.Graphics.DrawRectangle(Pens.Blue, bounds)
        End Sub
        
        ' Handle the QueryAccessibilityHelp event.
        Private Sub ChartControl_QueryAccessibilityHelp(sender As Object, _
                           e As System.Windows.Forms.QueryAccessibilityHelpEventArgs) Handles MyBase.QueryAccessibilityHelp
            e.HelpString = "Displays chart data"
        End Sub 

        ' Handle the Click event for the chart. 
        ' Toggle the selection of whatever legend was clicked.     
        Private Sub ChartControl_Click(sender As Object, e As System.EventArgs) Handles MyBase.Click

            Dim pt As Point = Me.PointToClient(Control.MousePosition)
            If legend1.Bounds.Contains(pt) Then
                legend1.Selected = Not legend1.Selected
            Else
                If legend2.Bounds.Contains(pt) Then
                    legend2.Selected = Not legend2.Selected
                End If
            End If
        End Sub

        ' Get an array of the CurveLengends used in the Chart.
        Public ReadOnly Property Legends() As CurveLegend()
            Get
                Return New CurveLegend() {legend1, legend2}
            End Get
        End Property
        
        Protected Sub ExposeAccessibilityNotifyClients(ByVal accEvent As AccessibleEvents, ByVal childID As Integer)
            AccessibilityNotifyClients(accEvent, childID) 
        End Sub

        ' Inner Class ChartControlAccessibleObject represents accessible information 
        ' associated with the ChartControl.
        ' The ChartControlAccessibleObject is returned in the         ' ChartControl.CreateAccessibilityInstance override.
        Public Class ChartControlAccessibleObject
            Inherits Control.ControlAccessibleObject

            Private chartControl As ChartControl
            
            Public Sub New(ctrl As ChartControl)
                MyBase.New(ctrl)
                chartControl = ctrl
            End Sub
            
            ' Get the role for the Chart. This is used by accessibility programs.            
            Public Overrides ReadOnly Property Role() As AccessibleRole
                Get
                    Return System.Windows.Forms.AccessibleRole.Chart
                End Get
            End Property
            
            ' Get the state for the Chart. This is used by accessibility programs.            
            Public Overrides ReadOnly Property State() As AccessibleStates
                Get
                    Return AccessibleStates.ReadOnly
                End Get
            End Property                        
            
            ' The CurveLegend objects are "child" controls in terms of accessibility so 
            ' return the number of ChartLengend objects.            
            Public Overrides Function GetChildCount() As Integer
                Return chartControl.Legends.Length
            End Function 
            
            ' Get the Accessibility object of the child CurveLegend idetified by index.
            Public Overrides Function GetChild(index As Integer) As AccessibleObject
                If index >= 0 And index < chartControl.Legends.Length Then
                    Return chartControl.Legends(index).AccessibilityObject
                End If
                Return Nothing
            End Function 
            
            ' Helper function that is used by the CurveLegend's accessibility object
            ' to navigate between sibiling controls. Specifically, this function is used in
            ' the CurveLegend.CurveLegendAccessibleObject.Navigate function.
            Friend Function NavigateFromChild(child As CurveLegend.CurveLegendAccessibleObject, _
                                            navdir As AccessibleNavigation) As AccessibleObject
                Select Case navdir
                    Case AccessibleNavigation.Down, AccessibleNavigation.Next
                            Return GetChild(child.ID + 1)
                    
                    Case AccessibleNavigation.Up, AccessibleNavigation.Previous
                            Return GetChild(child.ID - 1)
                End Select
                Return Nothing
            End Function            

            ' Helper function that is used by the CurveLegend's accessibility object
            ' to select a specific CurveLegend control. Specifically, this function is used 
            ' in the CurveLegend.CurveLegendAccessibleObject.Select function.            
            Friend Sub SelectChild(child As CurveLegend.CurveLegendAccessibleObject, selection As AccessibleSelection)
                Dim childID As Integer = child.ID
                
                ' Determine which selection action should occur, based on the
                ' AccessibleSelection value.
                If (selection And AccessibleSelection.TakeSelection) <> 0 Then
                    Dim i As Integer
                    For i = 0 To chartControl.Legends.Length - 1
                        If i = childID Then
                            chartControl.Legends(i).Selected = True
                        Else
                            chartControl.Legends(i).Selected = False
                        End If
                    Next i
                    
                    ' AccessibleSelection.AddSelection means that the CurveLegend will be selected.
                    If (selection And AccessibleSelection.AddSelection) <> 0 Then
                        chartControl.Legends(childID).Selected = True
                    End If

                    ' AccessibleSelection.AddSelection means that the CurveLegend will be unselected.                    
                    If (selection And AccessibleSelection.RemoveSelection) <> 0 Then
                        chartControl.Legends(childID).Selected = False
                    End If
                End If
            End Sub
        End Class

        ' Inner Class that represents a legend for a curve in the chart.
        Public Class CurveLegend
            Private m_name As String
            Private chart As ChartControl
            Private accObj As CurveLegendAccessibleObject
            Private m_selected As Boolean = True
            Private m_location As Point
            
            Public Sub New(chart As ChartControl, name As String)
                Me.chart = chart
                Me.m_name = name
            End Sub

            ' Gets the accessibility object for the curve legend.            
            Public ReadOnly Property AccessibilityObject() As AccessibleObject
                Get
                    If accObj Is Nothing Then
                        accObj = New CurveLegendAccessibleObject(Me)
                    End If
                    Return accObj
                End Get
            End Property
            
            ' Gets the bounds for the curve legend.            
            Public ReadOnly Property Bounds() As Rectangle
                Get
                    Return New Rectangle(Location, Size)
                End Get
            End Property

            ' Gets or sets the location for the curve legend.            
            Public Property Location() As Point
                Get
                    Return m_location
                End Get
                Set
                    m_location = value
                    chart.Invalidate()

                    ' Notifies the chart of the location change. This is used for
                    ' the accessibility information. AccessibleEvents.LocationChange
                    ' tells the chart the reason for the notification.
                    chart.ExposeAccessibilityNotifyClients(AccessibleEvents.LocationChange, _
                            CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
                End Set
            End Property
            
            ' Gets or sets the Name for the curve legend.            
            Public Property Name() As String
                Get
                    Return m_name
                End Get
                Set
                    If m_name <> value Then
                        m_name = value
                        chart.Invalidate()

                        ' Notifies the chart of the name change. This is used for
                        ' the accessibility information. AccessibleEvents.NameChange
                        ' tells the chart the reason for the notification. 
                        chart.ExposeAccessibilityNotifyClients(AccessibleEvents.NameChange, _
                                CType(AccessibilityObject, CurveLegendAccessibleObject).ID)
                    End If
                End Set
            End Property
            
            ' Gets or sets the Selected state for the curve legend.            
            Public Property Selected() As Boolean
                Get
                    Return m_selected
                End Get
                Set
                    If m_selected <> value Then
                        m_selected = value
                        chart.Invalidate()

                        ' Notifies the chart of the selection value change. This is used for
                        ' the accessibility information. The AccessibleEvents value varies
                        ' on whether the selection is true (AccessibleEvents.SelectionAdd) or 
                        ' false (AccessibleEvents.SelectionRemove). 
                        If m_selected Then
                            chart.ExposeAccessibilityNotifyClients(AccessibleEvents.SelectionAdd, _
                                    CType(AccessibilityObject, CurveLegendAccessibleObject).ID) 
                        Else
                            chart.ExposeAccessibilityNotifyClients(AccessibleEvents.SelectionRemove, _
                                    CType(AccessibilityObject, CurveLegendAccessibleObject).ID) 
                        End If
                    End If
                End Set
            End Property
            
            ' Gets the Size for the curve legend.            
            Public ReadOnly Property Size() As Size
                Get
                    Dim legendHeight As Integer = chart.Font.Height + 4
                    Dim g As Graphics = chart.CreateGraphics()
                    Dim legendWidth As Integer = CInt(g.MeasureString(Name, chart.Font).Width) + 4
                    
                    Return New Size(legendWidth, legendHeight)
                End Get
            End Property
            
            
            ' Inner class CurveLegendAccessibleObject represents accessible information 
            ' associated with the CurveLegend object.
            Public Class CurveLegendAccessibleObject
                Inherits AccessibleObject

                Private curveLegend As CurveLegend
                
                Public Sub New(curveLegend As CurveLegend)
                    Me.curveLegend = curveLegend
                End Sub
                
                ' Private property that helps get the reference to the parent ChartControl.                
                Private ReadOnly Property ChartControl() As ChartControlAccessibleObject
                    Get
                        Return CType(Parent, ChartControlAccessibleObject)
                    End Get
                End Property

                ' Friend helper function that returns the ID for this CurveLegend.                
                Friend ReadOnly Property ID() As Integer
                    Get
                        Dim i As Integer
                        For i = 0 To (ChartControl.GetChildCount()) - 1
                            If ChartControl.GetChild(i) Is Me Then
                                Return i
                            End If
                        Next i
                        Return - 1
                    End Get
                End Property
                
                ' Gets the Bounds for the CurveLegend. This is used by accessibility programs.
                Public Overrides ReadOnly Property Bounds() As Rectangle
                    Get
                        ' The bounds is in screen coordinates.
                        Dim loc As Point = curveLegend.Location
                        Return New Rectangle(curveLegend.chart.PointToScreen(loc), curveLegend.Size)
                    End Get
                End Property

                ' Gets or sets the Name for the CurveLegend. This is used by accessibility programs.                
                Public Overrides Property Name() As String
                    Get
                        Return curveLegend.Name
                    End Get
                    Set
                        curveLegend.Name = value
                    End Set
                End Property
                
                ' Gets the Curve Legend Parent's Accessible object.
                ' This is used by accessibility programs.                
                Public Overrides ReadOnly Property Parent() As AccessibleObject
                    Get
                        Return curveLegend.chart.AccessibilityObject
                    End Get
                End Property
                
                ' Gets the role for the CurveLegend. This is used by accessibility programs.                
                Public Overrides ReadOnly Property Role() As AccessibleRole
                    Get
                        Return System.Windows.Forms.AccessibleRole.StaticText
                    End Get
                End Property

                ' Gets the state based on the selection for the CurveLegend. 
                ' This is used by accessibility programs.                
                Public Overrides ReadOnly Property State() As AccessibleStates
                    Get
                        Dim stateTemp As AccessibleStates = AccessibleStates.Selectable
                        If curveLegend.Selected Then
                            stateTemp = stateTemp Or AccessibleStates.Selected
                        End If
                        Return stateTemp
                    End Get
                End Property
                
                ' Navigates through siblings of this CurveLegend. This is used by accessibility programs.                
                Public Overrides Function Navigate(navdir As AccessibleNavigation) As AccessibleObject
                    ' Use the Friend NavigateFromChild helper function that exists
                    ' on ChartControlAccessibleObject.
                    Return ChartControl.NavigateFromChild(Me, navdir)
                End Function
                
                ' Selects or unselects this CurveLegend. This is used by accessibility programs.
                Public Overrides Sub [Select](selection As AccessibleSelection)

                    ' Use the internal SelectChild helper function that exists
                    ' on ChartControlAccessibleObject.
                    ChartControl.SelectChild(Me, selection)
                End Sub

            End Class

        End Class

    End Class

End Namespace 'ChartControlNameSpace

Açıklamalar

Erişilebilirlik uygulamaları, engelli kullanıcıların kullanılabilirliğini artırmak için uygulamanın özelliklerini ayarlayabilir.

Görme engelli kullanıcılar için yazılım ve işletim sistemi özelliklerini ihtiyaçlarına uyacak şekilde ayarlayabilirsiniz. Örneğin, metin ve resimleri büyütebilir ve bunları karşıtlık ile işleyebilirsiniz. Buna ek olarak, renk körlüğüne uygun renk kullanımıyla uyum sağlayabilirsiniz. Ciddi derecede görme engelli kullanıcılar için bilgisayarlara ekrandaki metni konuşmaya veya dinamik, yenilenebilir, Braille ekranına çeviren ekran inceleme yardımcılarıyla erişilebilir.

İşitme güçlüğü çeken kullanıcılar için, yanıp sönen araç çubuğu gibi görsel ipuçları kullanan programlar tasarlayabilirsiniz; veya konuşulan iletileri metin olarak görüntüleyebilirsiniz. Örneğin, SoundSentry Denetim Masası'daki bir erişilebilirlik seçeneği olan özellik, sistem her alarm sesi yaptığında görsel bir uyarı sağlar.

Hareket engelli kullanıcılar için klavye ve fare kullanımını geliştiren veya ortadan kaldıran denetimler tasarlayarak bilgisayar erişilebilirliğini geliştirebilirsiniz. Denetim Masası yardım sunar. Örneğin, gezinti için fare yerine sayısal tuş takımını kullanmak bir alternatiftir. adlı StickyKeysbaşka bir seçenek, aynı anda iki veya daha fazla tuşa (CTRL+P gibi) basılı tutamayan kullanıcıların aynı sonucu aynı anda bir tuş yazarak elde etmelerini sağlar.

Bilişsel ve dil engelli kullanıcılar için, gereksinimlerini daha iyi karşılayacak yazılım programları tasarlayabilirsiniz. Örneğin, dikkat çekici veya sevimli sıralama, karmaşık olmayan ekranlar, daha az sözcük ve ilkokul standartlarını hedefleyen bir okuma düzeyi kullanmak bu kullanıcılara yararlı olabilir.

Nöbet bozuklukları olan kullanıcılar için, nöbet kışkırtma düzenlerini ortadan kaldırmak için yazılım programları tasarlayabilirsiniz.

Erişilebilirlik uygulamaları hakkında bilgiler de dahil olmak üzere erişilebilirlik hakkında daha fazla bilgi için bkz. Windows Erişilebilirlik özellikleri.

Not

kullanmak AccessibleObjectiçin, .NET Framework yüklü derlemeye Accessibility bir başvuru eklemeniz gerekir. Windows Forms yalnızca Etkin Erişilebilirlik 2.0'i destekler.

Devralanlara Notlar

Bu sınıftan devraldığınızda, tüm üyeleri geçersiz kılabilirsiniz.

Oluşturucular

AccessibleObject()

AccessibleObject sınıfının yeni bir örneğini başlatır.

Özellikler

Bounds

Erişilebilir nesnenin konumunu ve boyutunu alır.

DefaultAction

Nesnenin varsayılan eylemini açıklayan bir dize alır. Tüm nesnelerin varsayılan eylemi yoktur.

Description

Belirtilen nesnenin görünümünü açıklayan bir dize alır. Tüm nesnelerin açıklaması yoktur.

Help

Nesnenin ne yaptığının veya nesnenin nasıl kullanıldığının açıklamasını alır.

KeyboardShortcut

Erişilebilir nesnenin kısayol tuşunu veya erişim tuşunu alır.

Name

Nesne adını alır veya ayarlar.

Parent

Erişilebilir bir nesnenin üst öğesini alır.

Role

Bu erişilebilir nesnenin rolünü alır.

State

Bu erişilebilir nesnenin durumunu alır.

Value

Erişilebilir bir nesnenin değerini alır veya ayarlar.

Yöntemler

CreateObjRef(Type)

Uzak bir nesneyle iletişim kurmak için kullanılan bir ara sunucu oluşturmak için gereken tüm ilgili bilgileri içeren bir nesne oluşturur.

(Devralındığı yer: MarshalByRefObject)
DoDefaultAction()

Bu erişilebilir nesneyle ilişkili varsayılan eylemi gerçekleştirir.

Equals(Object)

Belirtilen nesnenin geçerli nesneye eşit olup olmadığını belirler.

(Devralındığı yer: Object)
GetChild(Int32)

Belirtilen dizine karşılık gelen erişilebilir alt öğeyi alır.

GetChildCount()

Erişilebilir bir nesneye ait alt öğe sayısını alır.

GetFocused()

Klavye odağı olan nesneyi alır.

GetHashCode()

Varsayılan karma işlevi işlevi görür.

(Devralındığı yer: Object)
GetHelpTopic(String)

Bir Yardım konusu tanımlayıcısının tanımlayıcısını ve bu erişilebilir nesneyle ilişkili Yardım dosyasının yolunu alır.

GetLifetimeService()
Kullanımdan kalktı.

Bu örnek için yaşam süresi ilkesini denetleen geçerli yaşam süresi hizmet nesnesini alır.

(Devralındığı yer: MarshalByRefObject)
GetSelected()

Seçili durumdaki alt öğeyi alır.

GetType()

Type Geçerli örneğini alır.

(Devralındığı yer: Object)
HitTest(Int32, Int32)

Belirtilen ekran koordinatlarında alt nesneyi alır.

InitializeLifetimeService()
Kullanımdan kalktı.

Bu örneğin yaşam süresi ilkesini denetlemek için bir yaşam süresi hizmet nesnesi alır.

(Devralındığı yer: MarshalByRefObject)
MemberwiseClone()

Geçerli Objectöğesinin sığ bir kopyasını oluşturur.

(Devralındığı yer: Object)
MemberwiseClone(Boolean)

Geçerli MarshalByRefObject nesnenin sığ bir kopyasını oluşturur.

(Devralındığı yer: MarshalByRefObject)
Navigate(AccessibleNavigation)

Başka bir erişilebilir nesneye gider.

RaiseAutomationNotification(AutomationNotificationKind, AutomationNotificationProcessing, String)

UI otomasyonu bildirim olayını tetikler.

RaiseLiveRegionChanged()

LiveRegionChanged UI otomasyon olayını tetikler.

Select(AccessibleSelection)

Seçimi değiştirir veya erişilebilir nesnenin klavye odağını taşır.

ToString()

Geçerli nesneyi temsil eden dizeyi döndürür.

(Devralındığı yer: Object)
UseStdAccessibleObjects(IntPtr)

Bir nesneyi, nesnenin tutamacını temel alan bir AccessibleObject örneğiyle ilişkilendirir.

UseStdAccessibleObjects(IntPtr, Int32)

Bir nesneyi tanıtıcıyı ve nesnenin nesne kimliğini temel alan bir AccessibleObject örneğiyle ilişkilendirir.

Belirtik Arabirim Kullanımları

IAccessible.accChildCount

Bu nesneye ait alt arabirimlerin sayısını alır. Bu üyenin açıklaması için bkz accChildCount. .

IAccessible.accDoDefaultAction(Object)

Belirtilen nesnenin varsayılan eylemini gerçekleştirir. Tüm nesnelerin varsayılan eylemi yoktur. Bu üyenin açıklaması için bkz accDoDefaultAction(Object). .

IAccessible.accFocus

Klavye odağı olan nesneyi alır. Bu üyenin açıklaması için bkz accFocus. .

IAccessible.accHitTest(Int32, Int32)

Belirtilen ekran koordinatlarında alt nesneyi alır. Bu üyenin açıklaması için bkz accHitTest(Int32, Int32). .

IAccessible.accLocation(Int32, Int32, Int32, Int32, Object)

Nesnenin geçerli ekran konumunu alır. Bu üyenin açıklaması için bkz accLocation(Int32, Int32, Int32, Int32, Object). .

IAccessible.accNavigate(Int32, Object)

Geçerli nesneye göre erişilebilir bir nesneye gider. Bu üyenin açıklaması için bkz accNavigate(Int32, Object). .

IAccessible.accParent

Bu nesnenin üst erişilebilir nesnesini alır. Bu üyenin açıklaması için bkz accParent. .

IAccessible.accSelect(Int32, Object)

Seçimi değiştirir veya erişilebilir nesnenin klavye odağını taşır. Bu üyenin açıklaması için bkz accSelect(Int32, Object). .

IAccessible.accSelection

Erişilebilir bir nesnenin seçili alt nesnelerini alır. Bu üyenin açıklaması için bkz accSelection. .

IReflect.GetField(String, BindingFlags)

FieldInfo Belirtilen alana ve bağlama bayrağına karşılık gelen nesneyi alır. Bu üyenin açıklaması için bkz GetField(String, BindingFlags). .

IReflect.GetFields(BindingFlags)

Geçerli sınıfın FieldInfo tüm alanlarına karşılık gelen bir nesne dizisi alır. Bu üyenin açıklaması için bkz GetFields(BindingFlags). .

IReflect.GetMember(String, BindingFlags)

Tüm ortak üyelere veya belirtilen adla eşleşen tüm üyelere karşılık gelen bir nesne dizisi MemberInfo alır. Bu üyenin açıklaması için bkz GetMember(String, BindingFlags). .

IReflect.GetMembers(BindingFlags)

Tüm genel üyelere veya geçerli sınıfın MemberInfo tüm üyelerine karşılık gelen bir nesne dizisi alır. Bu üyenin açıklaması için bkz GetMembers(BindingFlags). .

IReflect.GetMethod(String, BindingFlags)

MethodInfo Belirtilen arama kısıtlamaları altında belirtilen yönteme karşılık gelen bir nesne alır. Bu üyenin açıklaması için bkz GetMethod(String, BindingFlags). .

IReflect.GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[])

MethodInfo Aşırı yüklenmiş yöntemler arasından seçim yapmak için bir Tür dizisi kullanarak belirtilen yönteme karşılık gelen bir nesneyi alır. Bu üyenin açıklaması için bkz GetMethod(String, BindingFlags, Binder, Type[], ParameterModifier[]). .

IReflect.GetMethods(BindingFlags)

Tüm genel yöntemler veya geçerli sınıfın MethodInfo tüm yöntemleriyle bir nesne dizisi alır. Bu üyenin açıklaması için bkz GetMethods(BindingFlags). .

IReflect.GetProperties(BindingFlags)

Tüm genel özelliklere veya geçerli sınıfın PropertyInfo tüm özelliklerine karşılık gelen bir nesne dizisi alır. Bu üyenin açıklaması için bkz GetProperties(BindingFlags). .

IReflect.GetProperty(String, BindingFlags)

PropertyInfo Belirtilen arama kısıtlamaları altında belirtilen özelliğe karşılık gelen bir nesneyi alır. Bu üyenin açıklaması için bkz GetProperty(String, BindingFlags). .

IReflect.GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[])

PropertyInfo Belirtilen arama kısıtlamalarına sahip belirtilen özelliğe karşılık gelen nesneyi alır. Bu üyenin açıklaması için bkz GetProperty(String, BindingFlags, Binder, Type, Type[], ParameterModifier[]). .

IReflect.InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[])

Belirtilen üyeyi çağırır. Bu üyenin açıklaması için bkz InvokeMember(String, BindingFlags, Binder, Object, Object[], ParameterModifier[], CultureInfo, String[]). .

IReflect.UnderlyingSystemType

Nesneyi temsil IReflect eden temel türü alır. Bu üyenin açıklaması için bkz UnderlyingSystemType. .

Şunlara uygulanır