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ToolboxItem Constructors

Definition

Initializes a new instance of the ToolboxItem class.

Overloads

ToolboxItem()

Initializes a new instance of the ToolboxItem class.

ToolboxItem(Type)

Initializes a new instance of the ToolboxItem class that creates the specified type of component.

Examples

The following code example demonstrates the use of the ToolboxItem constructor in a class derived from ToolboxItem for a custom toolbox item implementation. This code example is part of a larger example provided for the ToolboxItem class.

// Toolbox items must be serializable.
[Serializable]
class MyToolboxItem : ToolboxItem
{
    // The add components dialog in Visual Studio looks for a public
    // constructor that takes a type.
    public MyToolboxItem(Type toolType)
        : base(toolType)
    {
    }

    // And you must provide this special constructor for serialization.
    // If you add additional data to MyToolboxItem that you
    // want to serialize, you may override Deserialize and
    // Serialize methods to add that data.  
    MyToolboxItem(SerializationInfo info, StreamingContext context)
    {
        Deserialize(info, context);
    }

    // Let's override the creation code and pop up a dialog.
    protected override IComponent[] CreateComponentsCore(
        System.ComponentModel.Design.IDesignerHost host, 
        System.Collections.IDictionary defaultValues)
    {
        // Get the string we want to fill in the custom
        // user control.  If the user cancels out of the dialog,
        // return null or an empty array to signify that the 
        // tool creation was canceled.
        using (ToolboxItemDialog d = new ToolboxItemDialog())
        {
            if (d.ShowDialog() == DialogResult.OK)
            {
                string text = d.CreationText;

                IComponent[] comps =
                    base.CreateComponentsCore(host, defaultValues);
                // comps will have a single component: our data type.
                ((UserControl1)comps[0]).LabelText = text;
                return comps;
            }
            else
            {
                return null;
            }
        }
    }
}
<Serializable()> _
Class MyToolboxItem
    Inherits ToolboxItem

    ' The add components dialog in Visual Studio looks for a public
    ' constructor that takes a type.
    Public Sub New(ByVal toolType As Type)
        MyBase.New(toolType)
    End Sub


    ' And you must provide this special constructor for serialization.
    ' If you add additional data to MyToolboxItem that you
    ' want to serialize, you may override Deserialize and
    ' Serialize methods to add that data.  
    Sub New(ByVal info As SerializationInfo, _
        ByVal context As StreamingContext)
        Deserialize(info, context)
    End Sub


    ' Let's override the creation code and pop up a dialog.
    Protected Overrides Function CreateComponentsCore( _
        ByVal host As System.ComponentModel.Design.IDesignerHost, _
        ByVal defaultValues As System.Collections.IDictionary) _
        As IComponent()
        ' Get the string we want to fill in the custom
        ' user control.  If the user cancels out of the dialog,
        ' return null or an empty array to signify that the 
        ' tool creation was canceled.
        Using d As New ToolboxItemDialog()
            If d.ShowDialog() = DialogResult.OK Then
                Dim [text] As String = d.CreationText
                Dim comps As IComponent() = _
                    MyBase.CreateComponentsCore(host, defaultValues)
                ' comps will have a single component: our data type.
                CType(comps(0), UserControl1).LabelText = [text]
                Return comps
            Else
                Return Nothing
            End If
        End Using
    End Function
End Class

ToolboxItem()

Initializes a new instance of the ToolboxItem class.

public:
 ToolboxItem();
public ToolboxItem ();
Public Sub New ()

Examples

The following code example demonstrates the use of the ToolboxItem constructor in a class derived from ToolboxItem for a custom toolbox item implementation. This code example is part of a larger example provided for the ToolboxItem class.

// Toolbox items must be serializable.
[Serializable]
class MyToolboxItem : ToolboxItem
{
    // The add components dialog in Visual Studio looks for a public
    // constructor that takes a type.
    public MyToolboxItem(Type toolType)
        : base(toolType)
    {
    }

    // And you must provide this special constructor for serialization.
    // If you add additional data to MyToolboxItem that you
    // want to serialize, you may override Deserialize and
    // Serialize methods to add that data.  
    MyToolboxItem(SerializationInfo info, StreamingContext context)
    {
        Deserialize(info, context);
    }

    // Let's override the creation code and pop up a dialog.
    protected override IComponent[] CreateComponentsCore(
        System.ComponentModel.Design.IDesignerHost host, 
        System.Collections.IDictionary defaultValues)
    {
        // Get the string we want to fill in the custom
        // user control.  If the user cancels out of the dialog,
        // return null or an empty array to signify that the 
        // tool creation was canceled.
        using (ToolboxItemDialog d = new ToolboxItemDialog())
        {
            if (d.ShowDialog() == DialogResult.OK)
            {
                string text = d.CreationText;

                IComponent[] comps =
                    base.CreateComponentsCore(host, defaultValues);
                // comps will have a single component: our data type.
                ((UserControl1)comps[0]).LabelText = text;
                return comps;
            }
            else
            {
                return null;
            }
        }
    }
}
<Serializable()> _
Class MyToolboxItem
    Inherits ToolboxItem

    ' The add components dialog in Visual Studio looks for a public
    ' constructor that takes a type.
    Public Sub New(ByVal toolType As Type)
        MyBase.New(toolType)
    End Sub


    ' And you must provide this special constructor for serialization.
    ' If you add additional data to MyToolboxItem that you
    ' want to serialize, you may override Deserialize and
    ' Serialize methods to add that data.  
    Sub New(ByVal info As SerializationInfo, _
        ByVal context As StreamingContext)
        Deserialize(info, context)
    End Sub


    ' Let's override the creation code and pop up a dialog.
    Protected Overrides Function CreateComponentsCore( _
        ByVal host As System.ComponentModel.Design.IDesignerHost, _
        ByVal defaultValues As System.Collections.IDictionary) _
        As IComponent()
        ' Get the string we want to fill in the custom
        ' user control.  If the user cancels out of the dialog,
        ' return null or an empty array to signify that the 
        ' tool creation was canceled.
        Using d As New ToolboxItemDialog()
            If d.ShowDialog() = DialogResult.OK Then
                Dim [text] As String = d.CreationText
                Dim comps As IComponent() = _
                    MyBase.CreateComponentsCore(host, defaultValues)
                ' comps will have a single component: our data type.
                CType(comps(0), UserControl1).LabelText = [text]
                Return comps
            Else
                Return Nothing
            End If
        End Using
    End Function
End Class

Applies to

ToolboxItem(Type)

Initializes a new instance of the ToolboxItem class that creates the specified type of component.

public:
 ToolboxItem(Type ^ toolType);
public ToolboxItem (Type toolType);
public ToolboxItem (Type? toolType);
new System.Drawing.Design.ToolboxItem : Type -> System.Drawing.Design.ToolboxItem
Public Sub New (toolType As Type)

Parameters

toolType
Type

The type of IComponent that the toolbox item creates.

Exceptions

Examples

The following code example demonstrates the use of the ToolboxItem constructor in a class derived from ToolboxItem for a custom toolbox item implementation. This code example is part of a larger example provided for the ToolboxItem class.

// Toolbox items must be serializable.
[Serializable]
class MyToolboxItem : ToolboxItem
{
    // The add components dialog in Visual Studio looks for a public
    // constructor that takes a type.
    public MyToolboxItem(Type toolType)
        : base(toolType)
    {
    }

    // And you must provide this special constructor for serialization.
    // If you add additional data to MyToolboxItem that you
    // want to serialize, you may override Deserialize and
    // Serialize methods to add that data.  
    MyToolboxItem(SerializationInfo info, StreamingContext context)
    {
        Deserialize(info, context);
    }

    // Let's override the creation code and pop up a dialog.
    protected override IComponent[] CreateComponentsCore(
        System.ComponentModel.Design.IDesignerHost host, 
        System.Collections.IDictionary defaultValues)
    {
        // Get the string we want to fill in the custom
        // user control.  If the user cancels out of the dialog,
        // return null or an empty array to signify that the 
        // tool creation was canceled.
        using (ToolboxItemDialog d = new ToolboxItemDialog())
        {
            if (d.ShowDialog() == DialogResult.OK)
            {
                string text = d.CreationText;

                IComponent[] comps =
                    base.CreateComponentsCore(host, defaultValues);
                // comps will have a single component: our data type.
                ((UserControl1)comps[0]).LabelText = text;
                return comps;
            }
            else
            {
                return null;
            }
        }
    }
}
<Serializable()> _
Class MyToolboxItem
    Inherits ToolboxItem

    ' The add components dialog in Visual Studio looks for a public
    ' constructor that takes a type.
    Public Sub New(ByVal toolType As Type)
        MyBase.New(toolType)
    End Sub


    ' And you must provide this special constructor for serialization.
    ' If you add additional data to MyToolboxItem that you
    ' want to serialize, you may override Deserialize and
    ' Serialize methods to add that data.  
    Sub New(ByVal info As SerializationInfo, _
        ByVal context As StreamingContext)
        Deserialize(info, context)
    End Sub


    ' Let's override the creation code and pop up a dialog.
    Protected Overrides Function CreateComponentsCore( _
        ByVal host As System.ComponentModel.Design.IDesignerHost, _
        ByVal defaultValues As System.Collections.IDictionary) _
        As IComponent()
        ' Get the string we want to fill in the custom
        ' user control.  If the user cancels out of the dialog,
        ' return null or an empty array to signify that the 
        ' tool creation was canceled.
        Using d As New ToolboxItemDialog()
            If d.ShowDialog() = DialogResult.OK Then
                Dim [text] As String = d.CreationText
                Dim comps As IComponent() = _
                    MyBase.CreateComponentsCore(host, defaultValues)
                ' comps will have a single component: our data type.
                CType(comps(0), UserControl1).LabelText = [text]
                Return comps
            Else
                Return Nothing
            End If
        End Using
    End Function
End Class

Applies to