Sendsoutanechorequesttoaspecificcomputeronthenetwork(Pingfor.NET) Sends out an echo request to a specific computer on the network (Ping for .NET) [C#] Zepho Zep /PreviewSnippet.aspx?SnippetID=7b8d4b1a-72bc-4181-8bd7-7130c2a29b52 SurroundsWith

0) socket.Receive(pingResult, Math.Min(socket.Available, pingResult.Length), SocketFlags.None); // reset event readComplete.Reset(); // save start time DateTime timeSend = DateTime.Now; // complete ping command pingCommand[6] = lastSequenceNr++; SetChecksum(pingCommand); // send ping command, start receive command int iSend = socket.SendTo(pingCommand, new IPEndPoint(IPAddress.Parse(address), 0)); socket.BeginReceive(pingResult, 0, pingResult.Length, SocketFlags.None, new AsyncCallback(CallBack), null); // wait until data received or timeout if (readComplete.WaitOne(timeout, false)) { // check result if ((pingResult[20] == 0) && (pingCommand[4] == pingResult[24]) && (pingCommand[5] == pingResult[25]) && (pingCommand[6] == pingResult[26]) && (pingCommand[7] == pingResult[27])) // return time delay return DateTime.Now.Subtract(timeSend); } // return timeout return TimeSpan.MaxValue; } #endregion /*_______________________________________________________________*/ // methods: CallBack #region protected void CallBack(IAsyncResult result) { if (isOpen) { socket.EndReceive(result); readComplete.Set(); } } #endregion /*_______________________________________________________________*/ // methods: SetChecksum #region protected void SetChecksum(byte[] tel) { // reset old checksum tel[2] = 0; tel[3] = 0; // calculate new checksum uint cs = 0; for (int i = 0; i < pingCommand.Length; i = i+2) cs += BitConverter.ToUInt16(pingCommand, i); cs = ~((cs & 0xffffu) + (cs >> 16)); // set new checksum tel[2] = (byte) cs; tel[3] = (byte) (cs >> 8); } #endregion /*...............................................................*/ // fields // socket and event protected Socket socket; protected bool isOpen; protected ManualResetEvent readComplete; protected byte lastSequenceNr = 0; // ping command and result fields protected byte[] pingCommand; protected byte[] pingResult; } #endregion ]]>