Question

用VS2010中的C#获取本地IP出现问题，请帮忙找下原因

代码是：

private void btnShowIP_Click(object sender, EventArgs e)
{
IPHostEntry ipEntry = Dns.GetHostEntry(Dns.GetHostName());
string localIP = ipEntry.AddressList[0].ToString();
txtLocalIP.Text = localIP;
}
编译后，显示的IP为：fe80::bd22:43f8:c4f1:fa7b%20
但如果将Dns.GetHostEntry改为Dns.GetHostByName就是显示正确的IP：192.168.100.101，但编译器又说GetHostByName已经过时，应该替换为Dns.GetHostEntry。。。。。好纠结。

Answer 1

            IPHostEntry ipEntry = Dns.GetHostEntry(Dns.GetHostName());
            string localIP ="";//= ipEntry.AddressList[0].ToString();
            foreach (IPAddress item in ipEntry.AddressList)
            {
                localIP +=item.ToString();
                localIP += Environment.NewLine;
            }
            textBlock1.Text = localIP;

代码更改如上，你把所有的IP都列出来，不止是ipEntry.AddressList[0]

现在用的IP有IPV4和IPV6两种。旧版的函数只获取了IPV4。新版函数把这两种IP都获取了。

Answer 2

IPAddress[] arrIPAddresses = Dns.GetHostAddresses(Dns.GetHostName());
foreach (IPAddress ip in arrIPAddresses)
{
if (ip.AddressFamily.Equals(AddressFamily.InterNetwork))
{
this.ipAddress = ip.ToString();
}
}
用这个获取IP地址

Answer 3

用这个 我就是用这个。
public static string GetIPAddress()
{
string user_IP = string.Empty;
if (System.Web.HttpContext.Current.Request.ServerVariables["HTTP_VIA"] != null)
{
if (System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
{
user_IP = System.Web.HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString();
}
else
{
user_IP = System.Web.HttpContext.Current.Request.UserHostAddress;
}
}
else
{
user_IP = System.Web.HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"].ToString();
}
return user_IP;
}

Answer 4

获取IP地址

C#:
Request.UserHostAddress