Control.WndProc(Message) メソッド
定義
Windows メッセージを処理します。Processes Windows messages.
protected:
virtual void WndProc(System::Windows::Forms::Message % m);
protected virtual void WndProc (ref System.Windows.Forms.Message m);
abstract member WndProc : Message -> unit
override this.WndProc : Message -> unit
Protected Overridable Sub WndProc (ByRef m As Message)
パラメーター
例
次のコード例は、 WndProc 構造体で識別されたオペレーティングシステムメッセージを処理するメソッドのオーバーライドを示して Message います。The following code example demonstrates overriding the WndProc method to handle operating system messages identified in the Message structure. この例では、オペレーティングシステムの WM_ACTIVATEAPP メッセージが処理され、別のアプリケーションがアクティブになっていることがわかります。The WM_ACTIVATEAPP operating system message is handled in this example to know when another application is becoming active. 使用可能な、、およびの値については、次のトピックを参照してください Message.Msg Message.LParam Message.WParam 。See the following topics to understand the available Message.Msg, Message.LParam, and Message.WParam values. 実際の定数値は、Windows .h ヘッダーファイルにあります。Actual constant values can be found in the Windows.h header file.
using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Security::Permissions;
namespace csTempWindowsApplication1
{
public ref class Form1: public System::Windows::Forms::Form
{
private:
// Constant value was found in the "windows.h" header file.
static const Int32 WM_ACTIVATEAPP = 0x001C;
Boolean appActive;
public:
Form1()
{
appActive = true;
this->Size = System::Drawing::Size( 300, 300 );
this->Text = "Form1";
this->Font = gcnew System::Drawing::Font( "Microsoft Sans Serif",18.0F,System::Drawing::FontStyle::Bold,System::Drawing::GraphicsUnit::Point,((System::Byte)(0)) );
}
protected:
virtual void OnPaint( PaintEventArgs^ e ) override
{
// Paint a string in different styles depending on whether the
// application is active.
if ( appActive )
{
e->Graphics->FillRectangle( SystemBrushes::ActiveCaption, 20, 20, 260, 50 );
e->Graphics->DrawString( "Application is active", this->Font, SystemBrushes::ActiveCaptionText, 20, 20 );
}
else
{
e->Graphics->FillRectangle( SystemBrushes::InactiveCaption, 20, 20, 260, 50 );
e->Graphics->DrawString( "Application is Inactive", this->Font, SystemBrushes::ActiveCaptionText, 20, 20 );
}
}
[SecurityPermission(SecurityAction::Demand, Flags=SecurityPermissionFlag::UnmanagedCode)]
virtual void WndProc( Message% m ) override
{
// Listen for operating system messages.
switch ( m.Msg )
{
case WM_ACTIVATEAPP:
// The WParam value identifies what is occurring.
appActive = (int)m.WParam != 0;
// Invalidate to get new text painted.
this->Invalidate();
break;
}
Form::WndProc( m );
}
};
}
[STAThread]
int main()
{
Application::Run( gcnew csTempWindowsApplication1::Form1 );
}
using System;
using System.Drawing;
using System.Windows.Forms;
namespace csTempWindowsApplication1
{
public class Form1 : System.Windows.Forms.Form
{
// Constant value was found in the "windows.h" header file.
private const int WM_ACTIVATEAPP = 0x001C;
private bool appActive = true;
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
public Form1()
{
this.Size = new System.Drawing.Size(300,300);
this.Text = "Form1";
this.Font = new System.Drawing.Font("Microsoft Sans Serif", 18F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
}
protected override void OnPaint(PaintEventArgs e)
{
// Paint a string in different styles depending on whether the
// application is active.
if (appActive)
{
e.Graphics.FillRectangle(SystemBrushes.ActiveCaption,20,20,260,50);
e.Graphics.DrawString("Application is active", this.Font, SystemBrushes.ActiveCaptionText, 20,20);
}
else
{
e.Graphics.FillRectangle(SystemBrushes.InactiveCaption,20,20,260,50);
e.Graphics.DrawString("Application is Inactive", this.Font, SystemBrushes.ActiveCaptionText, 20,20);
}
}
[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
protected override void WndProc(ref Message m)
{
// Listen for operating system messages.
switch (m.Msg)
{
// The WM_ACTIVATEAPP message occurs when the application
// becomes the active application or becomes inactive.
case WM_ACTIVATEAPP:
// The WParam value identifies what is occurring.
appActive = (((int)m.WParam != 0));
// Invalidate to get new text painted.
this.Invalidate();
break;
}
base.WndProc(ref m);
}
}
}
Imports System.Drawing
Imports System.Windows.Forms
Namespace csTempWindowsApplication1
Public Class Form1
Inherits System.Windows.Forms.Form
' Constant value was found in the "windows.h" header file.
Private Const WM_ACTIVATEAPP As Integer = &H1C
Private appActive As Boolean = True
<STAThread()> _
Shared Sub Main()
Application.Run(New Form1())
End Sub
Public Sub New()
MyBase.New()
Me.Size = New System.Drawing.Size(300, 300)
Me.Text = "Form1"
Me.Font = New System.Drawing.Font("Microsoft Sans Serif", 18.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(0, Byte))
End Sub
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
' Paint a string in different styles depending on whether the
' application is active.
If (appActive) Then
e.Graphics.FillRectangle(SystemBrushes.ActiveCaption, 20, 20, 260, 50)
e.Graphics.DrawString("Application is active", Me.Font, SystemBrushes.ActiveCaptionText, 20, 20)
Else
e.Graphics.FillRectangle(SystemBrushes.InactiveCaption, 20, 20, 260, 50)
e.Graphics.DrawString("Application is Inactive", Me.Font, SystemBrushes.ActiveCaptionText, 20, 20)
End If
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)
' The WM_ACTIVATEAPP message occurs when the application
' becomes the active application or becomes inactive.
Case WM_ACTIVATEAPP
' The WParam value identifies what is occurring.
appActive = (m.WParam.ToInt32() <> 0)
' Invalidate to get new text painted.
Me.Invalidate()
End Select
MyBase.WndProc(m)
End Sub
End Class
End Namespace
注釈
メソッドによってフィルター処理された後、すべてのメッセージがメソッドに送信され WndProc PreProcessMessage ます。All messages are sent to the WndProc method after getting filtered through the PreProcessMessage method.
WndProc メソッドは、Windows WindowProc
関数に正確に対応しています。The WndProc method corresponds exactly to the Windows WindowProc
function. Windows メッセージの処理の詳細については、「 WindowProc 関数」を参照してください。For more information about processing Windows messages, see the WindowProc function.
注意 (継承者)
継承コントロールでは、基底クラスのメソッドを呼び出して、 WndProc(Message) 処理しないメッセージを処理する必要があります。Inheriting controls should call the base class's WndProc(Message) method to process any messages that they do not handle.