A Complete window program

Processing the Message:-

Every Message that window procedure receives is identified by a number, which message parameter to the window procedure. WndProc chooses to process only those messages.

WM_CREATE;

WM_PAINT;

WM_DESTROY;

These three processes drown by WndProc. It is important to call DefWindowProc for default processing.

Where to type this code:

·        Open VC++

·        Create new win32 application project

·        Select a simple win32 application

·        File view-> Source view-> open cpp file and code it.

//Complete Code for Creating a window

//It will display a string on the window “www.bcastuff.blogspot.com”

/*

This  application is created in win32 type

do not delete any previously added header files. 

*/

#include <windows.h>//Header File

#include "stdafx.h"

 LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

//this is Windows Procedure.

//defination of Main.

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,

                    PSTR szCmdLine, int iCmdShow)

{

     static TCHAR szAppName[] = TEXT ("HelloWin") ;

     HWND         hwnd ;

     MSG          msg ;

     WNDCLASS     wndclass ;

     wndclass.style         = CS_HREDRAW | CS_VREDRAW ;

     wndclass.lpfnWndProc   = WndProc ;

     wndclass.cbClsExtra    = 0 ;

     wndclass.cbWndExtra    = 0 ;

     wndclass.hInstance     = hInstance ;

     wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION) ;

     wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;

     wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;

     wndclass.lpszMenuName  = NULL ;

     wndclass.lpszClassName = szAppName ;

    //Rwgister the class

     RegisterClass (&wndclass);

    //Windows Create Function

     hwnd = CreateWindow (szAppName,                  // window class name

                          TEXT ("The Hello Program"), // window caption

                          WS_OVERLAPPEDWINDOW,        // window style

                          CW_USEDEFAULT,              // initial x position

                          CW_USEDEFAULT,              // initial y position

                          CW_USEDEFAULT,              // initial x size

                          CW_USEDEFAULT,              // initial y size

                          NULL,                       // parent window handle

                          NULL,                       // window menu handle

                          hInstance,                  // program instance handle

                          NULL) ;                     // creation parameters

    

//Show windows function

   ShowWindow (hwnd, iCmdShow) ;

     UpdateWindow (hwnd) ;

    

   //Message Loop  

     while (GetMessage (&msg, NULL, 0, 0))

     {

          TranslateMessage (&msg) ;

          DispatchMessage (&msg) ;

     }

     return msg.wParam ;

}

//Windows Procedure.

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)

{

     HDC         hdc ;

     PAINTSTRUCT ps ;

     RECT        rect ;

    

     switch (message)

     {

     case WM_CREATE:

         

          return 0 ;

     case WM_PAINT:

          hdc = BeginPaint (hwnd, &ps) ;

         

          GetClientRect (hwnd, &rect) ;

          //This line display the message

          TextOut(hdc,500,400 ,TEXT ("www.bcastuff.blogspot.com"), 27) ;

          EndPaint (hwnd, &ps) ;

          return 0 ;

         

     case WM_DESTROY:

          PostQuitMessage (0) ;

          return 0 ;

     }

     return DefWindowProc (hwnd, message, wParam, lParam) ;

}