Message Message Message Message Struct

定義

實作 Windows 訊息。Implements a Windows message.

public value class Message
public struct Message
type Message = struct
Public Structure Message
繼承

範例

下列程式碼範例將示範如何WndProc覆寫方法, 以處理中識別的Message作業系統訊息。The following code example demonstrates overriding the WndProc method to handle operating system messages identified in the Message. 在此範例中, 會處理 WM_ACTI加值稅EAPP 作業系統訊息, 以知道另一個應用程式變成作用中的時間。The WM_ACTIVATEAPP operating system message is handled in this example to know when another application is becoming active. 如需可用Message.Msg的、 Message.LParamMessage.WParam值的相關資訊, 請參閱MSG 結構檔。For information about the available Message.Msg, Message.LParam, and Message.WParam values, see the MSG Structure documentation. 如需實際常數值的詳細資訊, 請參閱訊息常數For information about the actual constant values, see Message Constants.

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

備註

Message結構會包裝 Windows 傳送的訊息。The Message structure wraps messages that Windows sends. 您可以使用這個結構來包裝訊息, 並將它指派給要分派的視窗程式。You can use this structure to wrap a message and assign it to the window procedure to be dispatched. 您也可以使用此結構來取得系統傳送給應用程式或控制項之訊息的相關資訊。You can also use this structure to get information about a message the system sends to your application or controls. 如需 Windows 訊息的詳細資訊, 請參閱訊息和訊息佇列For more information about Windows messages, see Messages and Message Queues.

您無法Message直接建立。You cannot create the Message directly. Create改用方法。Instead, use the Create method. 為了提高效率, Message會使用其現有的集區, 而不是具現Message化新的 (如果可能的話)。For the sake of efficiency, the Message uses its pool of existing Messages instead of instantiating a new one, if possible. 不過, 如果集Message區中沒有可用的, 則會具現化一個新的。However, if a Message is not available in the pool, a new one is instantiated.

屬性

HWnd HWnd HWnd HWnd

取得或設定訊息的視窗控制代碼 (Window Handle)。Gets or sets the window handle of the message.

LParam LParam LParam LParam

指定訊息的 LParam 欄位。Specifies the LParam field of the message.

Msg Msg Msg Msg

取得或設定訊息的 ID 編號。Gets or sets the ID number for the message.

Result Result Result Result

指定數值,回應處理訊息時該數值將傳回 Windows。Specifies the value that is returned to Windows in response to handling the message.

WParam WParam WParam WParam

取得或設定訊息的 WParam 欄位。Gets or sets the WParam field of the message.

方法

Create(IntPtr, Int32, IntPtr, IntPtr) Create(IntPtr, Int32, IntPtr, IntPtr) Create(IntPtr, Int32, IntPtr, IntPtr) Create(IntPtr, Int32, IntPtr, IntPtr)

建立新的 MessageCreates a new Message.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

判斷指定的物件是否等於目前的物件。Determines whether the specified object is equal to the current object.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

傳回這個執行個體的雜湊碼。Returns the hash code for this instance.

GetLParam(Type) GetLParam(Type) GetLParam(Type) GetLParam(Type)

取得 LParam 值,並將值轉換成物件。Gets the LParam value and converts the value to an object.

ToString() ToString() ToString() ToString()

傳回表示目前 StringMessageReturns a String that represents the current Message.

運算子

Equality(Message, Message) Equality(Message, Message) Equality(Message, Message) Equality(Message, Message)

判斷 Message 的兩個執行個體是否相等。Determines whether two instances of Message are equal.

Inequality(Message, Message) Inequality(Message, Message) Inequality(Message, Message) Inequality(Message, Message)

判斷 Message 的兩個執行個體是否不相等。Determines whether two instances of Message are not equal.

適用於

另請參閱