要获取屏幕的像素大小要使用GetSystemMetrics函数。下面就来看看这个函数的用法：
函数功能：用于得到被定义的
系统数据或者系统配置信息
函数原型：
// By MoreWindows( http://blog.csdn.net/MoreWindows )
int WINAPIGetSystemMetrics(
int nIndex
);
参数说明：
这个函数只有一个参数，不过这个参数可以取很多值。在WINUSER.H中有：
/*
* GetSystemMetrics() codes
*// MoreWindows( http://blog.csdn.net/MoreWindows )
*/
#define SM_CXSCREEN 0
#define SM_CYSCREEN 1
#define SM_CXVSCROLL 2
#define SM_CYHSCROLL 3
#define SM_CYCAPTION 4
#define SM_CXBORDER 5
#define SM_CYBORDER 6
#define SM_CXDLGFRAME 7
#define SM_CYDLGFRAME 8
#define SM_CYVTHUMB 9
#define SM_CXHTHUMB 10
#define SM_CXICON 11
#define SM_CYICON 12
#define SM_CXCURSOR 13
#define SM_CYCURSOR 14
#define SM_CYMENU 15
#define SM_CXFULLSCREEN 16
#define SM_CYFULLSCREEN 17
#define SM_CYKANJIWINDOW 18
#define SM_MOUSEPRESENT 19
#define SM_CYVSCROLL 20
#define SM_CXHSCROLL 21
#define SM_DEBUG 22
#define SM_SWAPBUTTON 23
#define SM_RESERVED1 24
#define SM_RESERVED2 25
#define SM_RESERVED3 26
#define SM_RESERVED4 27
#define SM_CXMIN 28
#define SM_CYMIN 29
#define SM_CXSIZE 30
#define SM_CYSIZE 31
#define SM_CXFRAME 32
#define SM_CYFRAME 33
#define SM_CXMINTRACK 34
#define SM_CYMINTRACK 35
#define SM_CXDOUBLECLK 36
#define SM_CYDOUBLECLK 37
#define SM_CXICONSPACING 38
#define SM_CYICONSPACING 39
#define SM_MENUDROPALIGNMENT 40
#define SM_PENWINDOWS 41
#define SM_DBCSENABLED 42
#define SM_CMOUSEBUTTONS 43
#if(WINVER >= 0x0400)
#define SM_CXFIXEDFRAME SM_CXDLGFRAME /* ;win40 name change */
#define SM_CYFIXEDFRAME SM_CYDLGFRAME /* ;win40 name change */
#define SM_CXSIZEFRAME SM_CXFRAME /* ;win40 name change */
#define SM_CYSIZEFRAME SM_CYFRAME /* ;win40 name change */
#define SM_SECURE 44
#define SM_CXEDGE 45
#define SM_CYEDGE 46
#define SM_CXMINSPACING 47
#define SM_CYMINSPACING 48
#define SM_CXSMICON 49
#define SM_CYSMICON 50
#define SM_CYSMCAPTION 51
#define SM_CXSMSIZE 52
#define SM_CYSMSIZE 53
#define SM_CXMENUSIZE 54
#define SM_CYMENUSIZE 55
#define SM_ARRANGE 56
#define SM_CXMINIMIZED 57
#define SM_CYMINIMIZED 58
#define SM_CXMAXTRACK 59
#define SM_CYMAXTRACK 60
#define SM_CXMAXIMIZED 61
#define SM_CYMAXIMIZED 62
#define SM_NETWORK 63
#define SM_CLEANBOOT 67
#define SM_CXDRAG 68
#define SM_CYDRAG 69
#endif /* WINVER >= 0x0400 */
#define SM_SHOWSOUNDS