Programming Windows Programming Guide-> Chapter 5 example program 6

/*_##################################### #######################################
_##
### Programming Windows Programming Design Guide-> Chapter 5 example program 6
_ ## Author: xwlee
_ ## Time: 2007.06.20
### Chang'an University
_ ## Development condition: win2003 SERVER + vc6.0
_##
_ ## Program 5-6 randrect
### Randrect. c file
### Programs that constantly display random rectangles
_ ## The program is only for verification
_##
_##
_ ## Randrect. c -- displays random rectangles
_ ## (C) Charles Petzold, 1998
_##
_####################################### ###################################*/

# Include <windows. h>

# Include <stdlib. h> // For the rand function

 

Lresult callback wndproc (hwnd, uint, wparam, lparam );

Void drawrectangle (hwnd );

 

Int cxclient, cyclient;

Int winapi winmain (hinstance, hinstance hprevinstance,

Pstr szcmdline, int icmdshow)

{

Static tchar szappname [] = text ("randrect ");

Hwnd;

MSG;

Wndclass;

Int I;

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;

If (! Registerclass (& wndclass ))

{

MessageBox (null, text ("this program requires Windows NT! "),

Szappname, mb_iconerror );

Return 0;

}

Hwnd = createwindow (szappname, text ("random rectangles "),

Ws_overlappedwindow,

Cw_usedefault, cw_usedefault,

Cw_usedefault, cw_usedefault,

Null, null, hinstance, null );

Showwindow (hwnd, icmdshow );

Updatewindow (hwnd );

While (true)

{

If (peekmessage (& MSG, null, 0, 0, pm_remove ))

{

If (msg. Message = wm_quit)

Break;

Translatemessage (& MSG );

Dispatchmessage (& MSG );

}

Else
{
For (I = 0; I <10000000; I ++ );

Drawrectangle (hwnd );

For (I = 0; I <10000000; I ++ );
}
}

Return msg. wparam;

}

 

Lresult callback wndproc (hwnd, uint imsg, wparam, lparam)

{

Switch (imsg)

{

Case wm_size:

Cxclient = loword (lparam );

Cyclient = hiword (lparam );

Return 0;

Case wm_destroy:

Postquitmessage (0 );

Return 0;

}

Return defwindowproc (hwnd, imsg, wparam, lparam );

}

Void drawrectangle (hwnd)

{

Hbrush;

HDC;

Rect;

If (cxclient = 0 | cyclient = 0)

Return;

Setrect (& rect, Rand () % cxclient, Rand () % cyclient,

Rand () % cxclient, Rand () % cyclient );

Hbrush = createsolidbrush (

RGB (RAND () % 256, Rand () % 256, Rand () % 256 ));

HDC = getdc (hwnd );

Fillrect (HDC, & rect, hbrush );

Releasedc (hwnd, HDC );

Deleteobject (hbrush );

}