Message Message Message Message Struct

Définition

Implémente un message Windows.Implements a Windows message.

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

Exemples

L’exemple de code suivant illustre la substitution de la WndProc méthode pour gérer les messages du système d’exploitation identifiés dans le Message.The following code example demonstrates overriding the WndProc method to handle operating system messages identified in the Message. Le message de système d’exploitation WM_ACTIVATEAPP est géré dans cet exemple pour savoir quand une autre application devient active.The WM_ACTIVATEAPP operating system message is handled in this example to know when another application is becoming active. Pour plus d’informations sur la disposition Message.Msg, Message.LParam, et Message.WParam valeurs, consultez le Structure MSG documentation.For information about the available Message.Msg, Message.LParam, and Message.WParam values, see the MSG Structure documentation. Pour plus d’informations sur les valeurs de constante, consultez Message constantes.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
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 'Main

        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

Remarques

Le Message structure encapsule les messages que Windows envoie.The Message structure wraps messages that Windows sends. Vous pouvez utiliser cette structure pour encapsuler un message et l’assigner à la procédure de fenêtre à distribuer.You can use this structure to wrap a message and assign it to the window procedure to be dispatched. Vous pouvez également utiliser cette structure pour obtenir des informations sur un message, le système envoie à votre application ou les contrôles.You can also use this structure to get information about a message the system sends to your application or controls. Pour plus d’informations sur les messages Windows, consultez Messages et les files d’attente.For more information about Windows messages, see Messages and Message Queues.

Vous ne pouvez pas créer le Message directement.You cannot create the Message directly. Au lieu de cela, utilisez le Create (méthode).Instead, use the Create method. Par souci d’efficacité, la Message utilise son pool existante Messages au lieu d’instancier un nouveau, si possible.For the sake of efficiency, the Message uses its pool of existing Messages instead of instantiating a new one, if possible. Toutefois, si un Message est non disponible dans le pool, un nouveau est instancié.However, if a Message is not available in the pool, a new one is instantiated.

Propriétés

HWnd HWnd HWnd HWnd

Obtient ou définit le handle de fenêtre du message.Gets or sets the window handle of the message.

LParam LParam LParam LParam

Spécifie le champ LParam du message.Specifies the LParam field of the message.

Msg Msg Msg Msg

Obtient ou définit le numéro d'identification du message.Gets or sets the ID number for the message.

Result Result Result Result

Spécifie la valeur retournée à Windows en réponse à la gestion du message.Specifies the value that is returned to Windows in response to handling the message.

WParam WParam WParam WParam

Obtient ou définit le champ WParam du message.Gets or sets the WParam field of the message.

Méthodes

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

Crée un Message.Creates a new Message.

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

Détermine si l'objet spécifié est identique à l'objet actuel.Determines whether the specified object is equal to the current object.

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

Retourne le code de hachage de cette instance.Returns the hash code for this instance.

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

Obtient la valeur LParam et convertit celle-ci en objet.Gets the LParam value and converts the value to an object.

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

Retourne une String qui représente l'Message actuel.Returns a String that represents the current Message.

Opérateurs

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

Détermine si les deux instances de Message sont identiques.Determines whether two instances of Message are equal.

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

Détermine si les deux instances de Message sont différentes.Determines whether two instances of Message are not equal.

S’applique à

Voir aussi