关于bool QImage::loadFromData 这个函数的问题 [复制链接]

由参考文档中：
bool QImage::loadFromData ( const uchar * buf, uint len, const char * format = 0 )

If format is specified, the loader attempts to read the image using the specified format. If format is not specified (which is the default), the loader reads a few bytes from the header to guess the file format.

其中format的解释不太明白啊！希望各位帮帮忙，知道的告诉我一下！谢谢～～

直接写后缀名, char*类型的．比如 png, bmp, jpg,xpm等

谢谢～～～