检查设备支持的像素格式

DescribePixelFormat 函数获取设备上下文的像素格式数据。 它还返回一个整数，该整数是设备上下文的最大像素格式索引。 以下代码示例演示如何使用该结果逐步检查设备支持的像素格式：

// local variables  
int                      iMax ; 
PIXELFORMATDESCRIPTOR    pfd; 
int                      iPixelFormat ; 
 
// initialize a pixel format index variable  
iPixelFormat = 1; 
 
// keep obtaining and examining pixel format data...  
do { 
    // try to obtain some pixel format data  
    iMax = DescribePixelFormat(hdc, iPixelFormat, sizeof(pfd), &pfd); 
 
    // if there was some problem with that...   
    if (iMax == 0) 
     
        // return indicating failure  
        return(FALSE); 
     
    // we have successfully obtained pixel format data  
 
    // let's examine the pixel format data...  
    myPixelFormatExaminer (&pfd); 
    }  
 
// ...until we've looked at all the device context's pixel formats  
while (++iPixelFormat <= iMax);