NativeWindow Klasse

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Stellt eine Kapselung auf niedriger Ebene eines Fensterhandles und einer Fensterprozedur bereit.

public ref class NativeWindow : MarshalByRefObject
public ref class NativeWindow : MarshalByRefObject, System::Windows::Forms::IWin32Window
public class NativeWindow : MarshalByRefObject
public class NativeWindow : MarshalByRefObject, System.Windows.Forms.IWin32Window
type NativeWindow = class
    inherit MarshalByRefObject
type NativeWindow = class
    inherit MarshalByRefObject
    interface IWin32Window
Public Class NativeWindow
Inherits MarshalByRefObject
Public Class NativeWindow
Inherits MarshalByRefObject
Implements IWin32Window
Vererbung
Object
MarshalByRefObject
NativeWindow
Implementiert
IWin32Window

Beispiele

Im folgenden Codebeispiel wird das Abfangen von Betriebssystemfenstermeldungen in einer Fensterprozedur und das Erstellen eines Fensters mit einem bestimmten Namen der Betriebssystemfensterklasse veranschaulicht. Im Beispiel werden zwei Klassen erstellt, die von NativeWindow dieser Aufgabe erben.

Die MyNativeWindowListener Klasse ist in die Fensterprozedur des Formulars eingebunden, das an den Konstruktor übergeben wird, und setzt die WndProc Methode außer Kraft, um die WM_ACTIVATEAPP Fenstermeldung abzufangen. Die Klasse veranschaulicht die Verwendung der AssignHandle Fensterhandle und ReleaseHandle methoden, um das verwendete Fensterhandle NativeWindow zu identifizieren. Das Handle wird basierend auf den Control.HandleCreated Ereignissen zugewiesen Control.HandleDestroyed . Wenn die WM_ACTIVATEAPP Fensternachricht empfangen wird, ruft die Klasse die form1.ApplicationActivated Methode auf.

Die MyNativeWindow Klasse erstellt ein neues Fenster mit dem ClassName Satz auf BUTTON. Die Klasse veranschaulicht die Verwendung der CreateHandle Methode und das Überschreiben der WndProc Methode zum Abfangen von Empfangenen Fenstermeldungen.

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Runtime::InteropServices;
ref class MyNativeWindowListener;
ref class MyNativeWindow;

// Summary description for Form1.
ref class Form1: public System::Windows::Forms::Form
{
private:
   MyNativeWindowListener^ nwl;
   MyNativeWindow^ nw;

internal:
   void ApplicationActived( bool ApplicationActivated )
   {
      // The application has been activated or deactivated
      #if defined(DEBUG)
      System::Diagnostics::Debug::WriteLine( "Application Active = {0}", ApplicationActivated.ToString() );
      #endif
   }


public:
   Form1();
};

// NativeWindow class to listen to operating system messages.
ref class MyNativeWindowListener: public NativeWindow
{
private:

   // Constant value was found in the S"windows.h" header file.
   literal int WM_ACTIVATEAPP = 0x001C;
   Form1^ parent;

public:
   MyNativeWindowListener( Form1^ parent )
   {
      parent->HandleCreated += gcnew EventHandler( this, &MyNativeWindowListener::OnHandleCreated );
      parent->HandleDestroyed += gcnew EventHandler( this, &MyNativeWindowListener::OnHandleDestroyed );
      this->parent = parent;
   }

internal:

   // Listen for the control's window creation and then hook into it.
   void OnHandleCreated( Object^ sender, EventArgs^ /*e*/ )
   {
      // Window is now created, assign handle to NativeWindow.
      AssignHandle( (dynamic_cast<Form1^>(sender))->Handle );
   }

   void OnHandleDestroyed( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      // Window was destroyed, release hook.
      ReleaseHandle();
   }

protected:

   virtual void WndProc( Message %m ) override
   {
      // Listen for operating system messages
      switch ( m.Msg )
      {
         case WM_ACTIVATEAPP:

            // Notify the form that this message was received.
            // Application is activated or deactivated,
            // based upon the WParam parameter.
            parent->ApplicationActived( ((int)m.WParam != 0) );
            break;
      }
      NativeWindow::WndProc( m );
   }

};

// MyNativeWindow class to create a window given a class name.
ref class MyNativeWindow: public NativeWindow
{
private:

   // Constant values were found in the S"windows.h" header file.
   literal int WS_CHILD = 0x40000000,WS_VISIBLE = 0x10000000,WM_ACTIVATEAPP = 0x001C;
   int windowHandle;

public:
   MyNativeWindow( Form^ parent )
   {
      CreateParams^ cp = gcnew CreateParams;

      // Fill in the CreateParams details.
      cp->Caption = "Click here";
      cp->ClassName = "Button";

      // Set the position on the form
      cp->X = 100;
      cp->Y = 100;
      cp->Height = 100;
      cp->Width = 100;

      // Specify the form as the parent.
      cp->Parent = parent->Handle;

      // Create as a child of the specified parent
      cp->Style = WS_CHILD | WS_VISIBLE;

      // Create the actual window
      this->CreateHandle( cp );
   }

protected:

   // Listen to when the handle changes to keep the variable in sync

   virtual void OnHandleChange() override
   {
      windowHandle = (int)this->Handle;
   }

   virtual void WndProc( Message % m ) override
   {
      // Listen for messages that are sent to the button window. Some messages are sent
      // to the parent window instead of the button's window.
      switch ( m.Msg )
      {
         case WM_ACTIVATEAPP:
            
            // Do something here in response to messages
            break;
      }
      NativeWindow::WndProc( m );
   }
};

Form1::Form1()
{
   this->Size = System::Drawing::Size( 300, 300 );
   this->Text = "Form1";
   nwl = gcnew MyNativeWindowListener( this );
   nw = gcnew MyNativeWindow( this );
}

// The main entry point for the application.

[STAThread]
int main()
{
   Application::Run( gcnew Form1 );
}

using System;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace NativeWindowApplication
{
    // Summary description for Form1.
    public class Form1 : System.Windows.Forms.Form
    {
        private MyNativeWindowListener nwl;
        private MyNativeWindow nw;

        internal void ApplicationActivated(bool ApplicationActivated)
        {
            // The application has been activated or deactivated
            System.Diagnostics.Debug.WriteLine("Application Active = " + ApplicationActivated.ToString());
        }

        private Form1()
        {
            this.Size = new System.Drawing.Size(300, 300);
            this.Text = "Form1";

            nwl = new MyNativeWindowListener(this);
            nw = new MyNativeWindow(this);
        }

        // The main entry point for the application.
        [STAThread]
        static void Main()
        {
            Application.Run(new Form1());
        }
    }

    // NativeWindow class to listen to operating system messages.
    internal class MyNativeWindowListener : NativeWindow
    {
        // Constant value was found in the "windows.h" header file.
        private const int WM_ACTIVATEAPP = 0x001C;

        private Form1 parent;

        public MyNativeWindowListener(Form1 parent)
        {

            parent.HandleCreated += new EventHandler(this.OnHandleCreated);
            parent.HandleDestroyed += new EventHandler(this.OnHandleDestroyed);
            this.parent = parent;
        }

        // Listen for the control's window creation and then hook into it.
        internal void OnHandleCreated(object sender, EventArgs e)
        {
            // Window is now created, assign handle to NativeWindow.
            AssignHandle(((Form1)sender).Handle);
        }
        internal void OnHandleDestroyed(object sender, EventArgs e)
        {
            // Window was destroyed, release hook.
            ReleaseHandle();
        }

        protected override void WndProc(ref Message m)
        {
            // Listen for operating system messages

            switch (m.Msg)
            {
                case WM_ACTIVATEAPP:

                    // Notify the form that this message was received.
                    // Application is activated or deactivated, 
                    // based upon the WParam parameter.
                    parent.ApplicationActivated(((int)m.WParam != 0));

                    break;
            }
            base.WndProc(ref m);
        }
    }

    // MyNativeWindow class to create a window given a class name.
    internal class MyNativeWindow : NativeWindow
    {

        // Constant values were found in the "windows.h" header file.
        private const int WS_CHILD = 0x40000000,
                          WS_VISIBLE = 0x10000000,
                          WM_ACTIVATEAPP = 0x001C;

        private int windowHandle;

        public MyNativeWindow(Form parent)
        {

            CreateParams cp = new CreateParams();

            // Fill in the CreateParams details.
            cp.Caption = "Click here";
            cp.ClassName = "Button";

            // Set the position on the form
            cp.X = 100;
            cp.Y = 100;
            cp.Height = 100;
            cp.Width = 100;

            // Specify the form as the parent.
            cp.Parent = parent.Handle;

            // Create as a child of the specified parent
            cp.Style = WS_CHILD | WS_VISIBLE;

            // Create the actual window
            this.CreateHandle(cp);
        }

        // Listen to when the handle changes to keep the variable in sync
        protected override void OnHandleChange()
        {
            windowHandle = (int)this.Handle;
        }

        protected override void WndProc(ref Message m)
        {
            // Listen for messages that are sent to the button window. Some messages are sent
            // to the parent window instead of the button's window.

            switch (m.Msg)
            {
                case WM_ACTIVATEAPP:
                    // Do something here in response to messages
                    break;
            }
            base.WndProc(ref m);
        }
    }
}

Imports System.Drawing
Imports System.Windows.Forms
Imports System.Runtime.InteropServices

<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
Public Class Form1
    Inherits System.Windows.Forms.Form

    Private nwl As MyNativeWindowListener
    Private nw As MyNativeWindow

    Friend Sub ApplicationActivated(ByVal ApplicationActivated As Boolean)
        ' The application has been activated or deactivated
        System.Diagnostics.Debug.WriteLine("Application Active = " + ApplicationActivated.ToString())
    End Sub

    Private Sub New()
        MyBase.New()

        Me.Size = New System.Drawing.Size(300, 300)
        Me.Text = "Form1"

        nwl = New MyNativeWindowListener(Me)
        nw = New MyNativeWindow(Me)

    End Sub

    Public Shared Sub Main()
        Application.Run(New Form1())
    End Sub
End Class

' NativeWindow class to listen to operating system messages.
Friend Class MyNativeWindowListener
    Inherits NativeWindow

    ' Constant value was found in the "windows.h" header file.
    Private Const WM_ACTIVATEAPP As Integer = &H1C

    Private parent As Form1

    Public Sub New(ByVal parent As Form1)

        AddHandler parent.HandleCreated, AddressOf Me.OnHandleCreated
        AddHandler parent.HandleDestroyed, AddressOf Me.OnHandleDestroyed
        Me.parent = parent
    End Sub

    ' Listen for the control's window creation and hook into it.    
    Private Sub OnHandleCreated(ByVal sender As Object, ByVal e As EventArgs)
        ' Window is now created, assign handle to NativeWindow.
        AssignHandle(CType(sender, Form).Handle)
    End Sub

    Private Sub OnHandleDestroyed(ByVal sender As Object, ByVal e As EventArgs)
        ' Window was destroyed, release hook.
        ReleaseHandle()
    End Sub

    <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
        Protected Overrides Sub WndProc(ByRef m As Message)
        ' Listen for operating system messages

        Select Case (m.Msg)
            Case WM_ACTIVATEAPP

                ' Notify the form that this message was received.
                ' Application is activated or deactivated, 
                ' based upon the WParam parameter.
                parent.ApplicationActivated(m.WParam.ToInt32() <> 0)

        End Select

        MyBase.WndProc(m)
    End Sub
End Class

' MyNativeWindow class to create a window given a class name.
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
Friend Class MyNativeWindow
    Inherits NativeWindow

    ' Constant values were found in the "windows.h" header file.
    Private Const WS_CHILD As Integer = &H40000000, _
                  WS_VISIBLE As Integer = &H10000000, _
                  WM_ACTIVATEAPP As Integer = &H1C

    Private windowHandle As Integer

    Public Sub New(ByVal parent As Form)

        Dim cp As CreateParams = New CreateParams()

        ' Fill in the CreateParams details.
        cp.Caption = "Click here"
        cp.ClassName = "Button"

        ' Set the position on the form
        cp.X = 100
        cp.Y = 100
        cp.Height = 100
        cp.Width = 100

        ' Specify the form as the parent.
        cp.Parent = parent.Handle

        ' Create as a child of the specified parent
        cp.Style = WS_CHILD Or WS_VISIBLE

        ' Create the actual window
        Me.CreateHandle(cp)
    End Sub

    ' Listen to when the handle changes to keep the variable in sync
    <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
    Protected Overrides Sub OnHandleChange()
        windowHandle = Me.Handle.ToInt32()
    End Sub

    <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
        Protected Overrides Sub WndProc(ByRef m As Message)
        ' Listen for messages that are sent to the button window. Some messages are sent
        ' to the parent window instead of the button's window.

        Select Case (m.Msg)
            Case WM_ACTIVATEAPP
                ' Do something here in response to messages
        End Select

        MyBase.WndProc(m)
    End Sub

End Class

Hinweise

Diese Klasse verwaltet automatisch die Fensterklassenerstellung und -registrierung.

Ein Fenster ist nicht für die Garbage Collection berechtigt, wenn es einem Fensterhandle zugeordnet ist. Um eine ordnungsgemäße Garbage Collection sicherzustellen, müssen Handles entweder manuell mithilfe DestroyHandle oder freigegeben werden.ReleaseHandle

Note

Die ReleaseHandle Methode wird aufgerufen, wenn die WM_NCDESTROY Nachricht verarbeitet wird. Dies bedeutet, dass es Fälle gibt, in denen Sie nicht manuell anrufen ReleaseHandlemüssen, aber es empfiehlt sich, dies zu tun.

Die NativeWindow Klasse stellt die folgenden Eigenschaften und Methoden zum Verwalten von Handles bereit: Handle, , CreateHandle, AssignHandle, , DestroyHandleund ReleaseHandle.

Konstruktoren

Name Beschreibung
NativeWindow()

Initialisiert eine Instanz der NativeWindow Klasse.

Eigenschaften

Name Beschreibung
Handle

Ruft das Handle für dieses Fenster ab.

Methoden

Name Beschreibung
AssignHandle(IntPtr)

Weist diesem Fenster ein Handle zu.
CreateHandle(CreateParams)

Erstellt ein Fenster und dessen Handle mit den angegebenen Erstellungsparametern.
CreateObjRef(Type)

Erstellt ein Objekt, das alle relevanten Informationen enthält, die zum Generieren eines Proxys erforderlich sind, der für die Kommunikation mit einem Remoteobjekt verwendet wird.

(Geerbt von MarshalByRefObject)
DefWndProc(Message)

Ruft die diesem Fenster zugeordnete Standardfensterprozedur auf.
DestroyHandle()

Zerstört das Fenster und dessen Ziehpunkt.
Equals(Object)

Bestimmt, ob das angegebene Objekt gleich dem aktuellen Objekt ist.

(Geerbt von Object)
Finalize()

Gibt die ressourcen frei, die diesem Fenster zugeordnet sind.
FromHandle(IntPtr)

Ruft das Fenster ab, das dem angegebenen Handle zugeordnet ist.
GetHashCode()

Dient als Standardhashfunktion.

(Geerbt von Object)
GetLifetimeService()

Ruft das aktuelle Lebensdauerdienstobjekt ab, das die Lebensdauerrichtlinie für diese Instanz steuert.

(Geerbt von MarshalByRefObject)
GetType()

Ruft die Type der aktuellen Instanz ab.

(Geerbt von Object)
InitializeLifetimeService()

Ruft ein Lebensdauerdienstobjekt ab, um die Lebensdauerrichtlinie für diese Instanz zu steuern.

(Geerbt von MarshalByRefObject)
MemberwiseClone()

Erstellt eine flache Kopie der aktuellen Object.

(Geerbt von Object)
MemberwiseClone(Boolean)

Erstellt eine flache Kopie des aktuellen MarshalByRefObject Objekts.

(Geerbt von MarshalByRefObject)
OnHandleChange()

Gibt eine Benachrichtigungsmethode an, die aufgerufen wird, wenn das Handle für ein Fenster geändert wird.
OnThreadException(Exception)

Wenn sie in einer abgeleiteten Klasse überschrieben wird, wird eine unbehandelte Thread-Ausnahme verwaltet.
ReleaseHandle()

Gibt das diesem Fenster zugeordnete Handle frei.
ToString()

Gibt eine Zeichenfolge zurück, die das aktuelle Objekt darstellt.

(Geerbt von Object)
WndProc(Message)

Ruft die diesem Fenster zugeordnete Standardfensterprozedur auf.

Gilt für:

Weitere Informationen