C#中有什么方法可以获取到使用者的IP嘛?

获取远程主机的MAC地址时,需要借用API函数SendARP.该函数使用ARP协议,向目的主机发送ARP包,利用返回并存储在高速缓存中的IP和MAC地址对,从而获取远程主机的MAC地址.

示例:
Int32 ldest= inet_addr(remoteIP); //目的ip
Int32 lhost= inet_addr(localIP); //本地ip

try
{
Int64 macinfo = new Int64();
Int32 len = 6;
int res = SendARP(ldest,0, ref macinfo, ref len); //发送ARP包
return Convert.ToString(macinfo,16);
}
catch(Exception err)
{
Console.WriteLine("Error:{0}",err.Message);
}
return 0.ToString();

但使用该方式获取MAC时有一个很大的限制,就是只能获取同网段的远程主机MAC地址.因为在标准网络协议下，ARP包是不能跨网段传输的，故想通过ARP协议是无法查询跨网段设备MAC地址的。

示例程序:

using System.Net;
using System;
using System.Management;
using System.Runtime.InteropServices;

public class getIP
{
[DllImport("Iphlpapi.dll")]
private static extern int SendARP(Int32 dest,Int32 host,ref Int64 mac,ref Int32 length);
[DllImport("Ws2_32.dll")]
private static extern Int32 inet_addr(string ip);

//获取本机的IP
public string getLocalIP()
{
string strHostName = Dns.GetHostName(); //得到本机的主机名
IPHostEntry ipEntry = Dns.GetHostByName(strHostName); //取得本机IP
string strAddr = ipEntry.AddressList[0].ToString();
return(strAddr);
}
//获取本机的MAC
public string getLocalMac()
{
string mac = null;
ManagementObjectSearcher query =new ManagementObjectSearcher("SELECT * FROM Win32_NetworkAdapterConfiguration") ;
ManagementObjectCollection queryCollection = query.Get();
foreach( ManagementObject mo in queryCollection )
{
if(mo["IPEnabled"].ToString() == "True")
mac = mo["MacAddress"].ToString();
}
return(mac);
}

//获取远程主机IP
public string[] getRemoteIP(string RemoteHostName)
{
IPHostEntry ipEntry = Dns.GetHostByName(RemoteHostName);
IPAddress[] IpAddr = ipEntry.AddressList;
string[] strAddr = new string[IpAddr.Length];
for (int i=0;i {
strAddr[i] = IpAddr[i].ToString();
}
return(strAddr);
}
//获取远程主机MAC
public string getRemoteMac(string localIP, string remoteIP)
{
Int32 ldest= inet_addr(remoteIP); //目的ip
Int32 lhost= inet_addr(localIP); //本地ip

try
{
Int64 macinfo = new Int64();
Int32 len = 6;
int res = SendARP(ldest,0, ref macinfo, ref len);
return Convert.ToString(macinfo,16);
}
catch(Exception err)
{
Console.WriteLine("Error:{0}",err.Message);
}
return 0.ToString();
}

public static void Main(string[] args)
{
getIP gi = new getIP();
Console.WriteLine("本地网卡信息:");
Console.WriteLine(gi.getLocalIP() + " - " + gi.getLocalMac());

Console.WriteLine("\n\r远程网卡信息:");
string[] temp = gi.getRemoteIP("scmobile-tj2");
for(int i=0;i {
Console.WriteLine(temp[i]);
}
Console.WriteLine(gi.getRemoteMac("192.168.0.3","192.168.0.1"));
}
}

C/S的话需要取得的是客户端的内网IP地址吧，
如果是的话，在客户端执行以下代码，并把结果返回给服务端即可：
IPAddress[] ips = Dns.GetHostAddresses(Dns.GetHostName());

以下是例子：

public static void DoGetHostAddresses(string hostname)
{
IPAddress[] ips;

ips = Dns.GetHostAddresses(hostname);

Console.WriteLine("GetHostAddresses({0}) returns:", hostname);

foreach (IPAddress ip in ips)
{
Console.WriteLine(" {0}", ip);
}
}

MessageBox.Show("IP:"+
System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList[0].ToString());

参考回答:
http://zhidao.baidu.com/question/30991349.html?si=1
回答者:karenback

我这里不是很好验证,通过外网服务器返回那个又比较麻烦...
如果有问题,可以给我发短信

IPAddress[] ip=new IPAddress[1];

ip = Dns.GetHostAddresses("HB");

MessageBox.Show(ip[0].ToString());

获取到的是内网IP