stdafx.h是预编译头文件,和您的工程是不是MFC应用程序没有关系。
要使用winsock的相关API函数,可以
#include <winsock2.h>
#pragma comment(lib, "WS2_32.lib")
Visual C++ enthusiast, like network programming and driver development. At present is being engaged in the WinCE/Windows Mobile platform embedded development.