1. 可以用WMI (Win2K & XP）：(首先要在VS.NET中创建一个项目，然后在添加引用中引用一个.net的装配件：System.Management.dll,这样你的项目才能使用WMI)with Windows 2000 & XP, UNDOCUMENTED: MSNdis_MediaConnectStatus - NdisMediaConnectStatus : (0 = connected?, 1 = not connected?)with Windows XP: Win32_NetworkAdapter - NetConnectionStatus : using System.Management;static void ReportConnection2000(){ ManagementClass mc = new ManagementClass( @'root\WMI', @'MSNdis_MediaConnectStatus', null ); ManagementObjectCollection moc = mc.GetInstances(); foreach( ManagementObject mo in moc ) { string name = (string) mo['InstanceName']; bool active = (bool) mo['Active']; uint status = (uint) mo['NdisMediaConnectStatus']; Console.WriteLine( ' {0}\n\tActive:{1} Media Status:{2}', name, active, status ); }}static void ReportConnectionXP(){ ManagementClass mc = new ManagementClass( @'Win32_NetworkAdapter' ); ManagementObjectCollection moc = mc.GetInstances(); foreach( ManagementObject mo in moc ) { string name = (string) mo['Name']; object val = mo['NetConnectionStatus']; if( val != null ) Console.WriteLine( ' {0}\n\tConnection Status:{1}', name, (ushort) val ); else Console.WriteLine( ' {0}\n', name ); }}如果返回0则表示连接；如果返回1则表示没连接；上面得到的是本地的连接状态；
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利用ping来得取： Process p = new Process();p.StartInfo .WorkingDirectory ='c:\\';p.StartInfo.FileName = 'ping.exe';p.StartInfo.Arguments='192.168.52.31';p.StartInfo.UseShellExecute = false;p.StartInfo.RedirectStandardOutput = true;p.StartInfo.CreateNoWindow = true;p.Start ();string output = p.StandardOutput.ReadToEnd();p.WaitForExit ();MessageBox.Show(output);//得到ping的输出值
