VC++ 判断指定IP或网址是否有效，这里需要三个参数：需要检查的网址对应的IP，你的网络ID,你的子网掩码，三者都输入无误后点击“测试”，如果网络连接会给出提示，网络ID是一个很复杂的参数，需要自己查找对应，或请高人指点。

-VC++ to determine the validity of the specified IP or web address, here takes three parameters: the URL to check the corresponding IP, your network ID, your subnet mask, all of which are entered correctly and click " test" , if the network connection prompting, the network ID is a very complex parameter, the corresponding need to find their own, or ask an expert advice.