在互联网上有几个地方告诉你如何获得一个IP地址。很多都像这个例子:

String strHostName = string.Empty;
// Getting Ip address of local machine...
// First get the host name of local machine.
strHostName = Dns.GetHostName();
Console.WriteLine("Local Machine's Host Name: " + strHostName);
// Then using host name, get the IP address list..
IPHostEntry ipEntry = Dns.GetHostEntry(strHostName);
IPAddress[] addr = ipEntry.AddressList;

for (int i = 0; i < addr.Length; i++)
{
    Console.WriteLine("IP Address {0}: {1} ", i, addr[i].ToString());
}
Console.ReadLine();

在这个例子中,我得到了几个IP地址,但我只对路由器分配给运行程序的计算机的IP地址感兴趣:例如,如果某人希望访问我计算机中的共享文件夹,我将给他的IP地址。

如果我没有连接到网络,我直接通过没有路由器的调制解调器连接到互联网,那么我希望得到一个错误。我如何才能看到我的计算机是否连接到网络与c#,如果它是然后得到局域网IP地址。


当前回答

string str="";

System.Net.Dns.GetHostName();

IPHostEntry ipEntry = System.Net.Dns.GetHostEntry(str);

IPAddress[] addr = ipEntry.AddressList;

string IP="Your Ip Address Is :->"+ addr[addr.Length - 1].ToString();

其他回答

这是最短的方法:

Dns.GetHostEntry(
    Dns.GetHostName()
).AddressList.AsEnumerable().Where(
    ip=>ip.AddressFamily.Equals(AddressFamily.InterNetwork)
).FirstOrDefault().ToString()

修改了compman2408的代码,以便能够遍历每个NetworkInterfaceType。

public static string GetLocalIPv4 (NetworkInterfaceType _type) {
    string output = null;
    foreach (NetworkInterface item in NetworkInterface.GetAllNetworkInterfaces ()) {
        if (item.NetworkInterfaceType == _type && item.OperationalStatus == OperationalStatus.Up) {
            foreach (UnicastIPAddressInformation ip in item.GetIPProperties ().UnicastAddresses) {
                if (ip.Address.AddressFamily == AddressFamily.InterNetwork) {
                    output = ip.Address.ToString ();
                }
            }
        }
    }
    return output;
}

你可以这样称呼它:

static void Main (string[] args) {
    // Get all possible enum values:
    var nitVals = Enum.GetValues (typeof (NetworkInterfaceType)).Cast<NetworkInterfaceType> ();

    foreach (var nitVal in nitVals) {
        Console.WriteLine ($"{nitVal} => {GetLocalIPv4 (nitVal) ?? "NULL"}");
    }
}
string str="";

System.Net.Dns.GetHostName();

IPHostEntry ipEntry = System.Net.Dns.GetHostEntry(str);

IPAddress[] addr = ipEntry.AddressList;

string IP="Your Ip Address Is :->"+ addr[addr.Length - 1].ToString();

我认为使用LINQ更容易:

Dns.GetHostEntry(Dns.GetHostName())
   .AddressList
   .First(x => x.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
   .ToString()
Dns.GetHostEntry(Dns.GetHostName()).AddressList[1].MapToIPv4() //returns 192.168.14.1