C# 获取当前ip

1。获取局域网ip      

IPAddress ipAddr = Dns.Resolve(Dns.GetHostName()).AddressList[0];//获得当前IP地址
string ip=ipAddr.ToString() ;

2。获取公网ip      

{
    string tempip = "";
    try
    {
        WebRequest wr = WebRequest.Create("http://www.ip138.com/ips138.asp");
        Stream s = wr.GetResponse().GetResponseStream();
        StreamReader sr = new StreamReader(s, Encoding.Default);
        string all = sr.ReadToEnd(); //读取网站的数据

        int start = all.IndexOf("您的IP地址是：[") + 9;
        int end = all.IndexOf("]", start);
        tempip = all.Substring(start, end - start);
        sr.Close();
        s.Close();
    }
    catch
    {
    }
    return tempip;
}

3.如果是ADSL上网，获取公网ip　　

string tempIP =string.Empty;
if (System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList.Length >1)
     tempIP = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList[1].ToString();