VC custom message response function postmessage usage example

This article illustrates the use of the VC custom message response function postmessage. Share with you for your reference. The specific implementation steps are as follows:

1. Add the following code to the resource-h file to specify a message of your own

#define WM_MY_MESSAGE      WM_USER + 100       //---------------------by tyds

2. In... The file of view.h is added as follows:

//{{AFX_MSG(CPostmessageView)

afx_msg void Ontydspostmessage();
afx_msg  void OnMyMessage(); //----- by tyds
//}}AFX_MSG

DECLARE_MESSAGE_MAP()

3. In... Add the following code to the view.cpp file

BEGIN_MESSAGE_MAP(CPostmessageView, CView)

//{{AFX_MSG_MAP(CPostmessageView)

ON_COMMAND(ID_tyds_postmessage, Ontydspostmessage)

ON_MESSAGE(WM_MY_MESSAGE, OnMyMessage)      //Add message mapping --by tyds 
 --
//}}AFX_MSG_MAP

// Standard printing commands

ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)

ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)

ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)

END_MESSAGE_MAP()
void CPostmessageView::Ontydspostmessage() 

{

MessageBox("begin post message!");

//PostMessage(WM_MY_MESSAGE);     // Here,  PostMessage SendMessage  Two differences 

SendMessage(WM_MY_MESSAGE);       //PostMessage is sent and returns, and SendMessage is sent and waits for execution before returning 

}
 Message corresponding function 

void   CPostmessageView::OnMyMessage() //Note that the parameters here may or may not depend on the return value as well as 

{
MessageBox("post msg finished!");

// return 0;

}

Hope that this article described the VC programming for you to help.