我想做个IP过滤功能!

刚才写了个笨办法，你看看：
string addr = Request.UserHostAddress; int index = addr.IndexOf(".", 0);
string firstAddr = addr.Substring(0, index); index++; int index2 = addr.IndexOf(".", index);
string secondAddr = addr.Substring(index, index2 - index); Response.Write(addr);
Response.Write("<br>");
Response.Write(firstAddr);
Response.Write("<br>");
Response.Write(secondAddr);