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

Dns.GetHostEntry(Dns.GetHostName()).AddressList[1].MapToIPv4() //returns 192.168.14.1

其他回答

这是我发现的最好的代码,以获得当前的IP,避免获得VMWare主机或其他无效的IP地址。

public string GetLocalIpAddress()
{
    UnicastIPAddressInformation mostSuitableIp = null;

    var networkInterfaces = NetworkInterface.GetAllNetworkInterfaces();

    foreach (var network in networkInterfaces)
    {
        if (network.OperationalStatus != OperationalStatus.Up)
            continue;

        var properties = network.GetIPProperties();

        if (properties.GatewayAddresses.Count == 0)
            continue;

        foreach (var address in properties.UnicastAddresses)
        {
            if (address.Address.AddressFamily != AddressFamily.InterNetwork)
                continue;

            if (IPAddress.IsLoopback(address.Address))
                continue;

            if (!address.IsDnsEligible)
            {
                if (mostSuitableIp == null)
                    mostSuitableIp = address;
                continue;
            }

            // The best IP is the IP got from DHCP server
            if (address.PrefixOrigin != PrefixOrigin.Dhcp)
            {
                if (mostSuitableIp == null || !mostSuitableIp.IsDnsEligible)
                    mostSuitableIp = address;
                continue;
            }

            return address.Address.ToString();
        }
    }

    return mostSuitableIp != null 
        ? mostSuitableIp.Address.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()

我还在努力获取正确的IP。

我在这里尝试了各种解决方案,但没有一个能达到我想要的效果。几乎所有提供的条件测试都没有使用地址。

这是对我有效的方法,希望能有所帮助……

var firstAddress = (from address in NetworkInterface.GetAllNetworkInterfaces().Select(x => x.GetIPProperties()).SelectMany(x => x.UnicastAddresses).Select(x => x.Address)
                    where !IPAddress.IsLoopback(address) && address.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork
                    select address).FirstOrDefault();

Console.WriteLine(firstAddress);
Imports System.Net
Imports System.Net.Sockets
Function LocalIP()
    Dim strHostName = Dns.GetHostName
    Dim Host = Dns.GetHostEntry(strHostName)
    For Each ip In Host.AddressList
        If ip.AddressFamily = AddressFamily.InterNetwork Then
            txtIP.Text = ip.ToString
        End If
    Next

    Return True
End Function

下面是同样的动作

Function LocalIP()

   Dim Host As String =Dns.GetHostEntry(Dns.GetHostName).AddressList(1).MapToIPv4.ToString

   txtIP.Text = Host

   Return True

End Function

使用linq表达式获取IP的其他方法:

public static List<string> GetAllLocalIPv4(NetworkInterfaceType type)
{
    return NetworkInterface.GetAllNetworkInterfaces()
                   .Where(x => x.NetworkInterfaceType == type && x.OperationalStatus == OperationalStatus.Up)
                   .SelectMany(x => x.GetIPProperties().UnicastAddresses)
                   .Where(x => x.Address.AddressFamily == AddressFamily.InterNetwork)
                   .Select(x => x.Address.ToString())
                   .ToList();
}