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在C#中实现Ping,代码如下:
using System;using System.Drawing;using System.Collections;using System.Data;using System.Net;using System.Net.Sockets;/// Ping类public class Ping{//声明常量const int SOCKET_ERROR = -1;const int ICMP_ECHO = 8;// 程序入口public static void Main(){ Ping p = new Ping(); Console.WriteLine("请输入要 Ping 的IP或者主机名字:"); string MyUrl = Console.ReadLine(); Console.WriteLine("正在 Ping " + MyUrl + " ……"); Console.Write(p.PingHost(MyUrl));}public string PingHost(string host){ // 声明 IPHostEntry IPHostEntry serverHE, fromHE; int nBytes = 0; int dwStart = 0, dwStop = 0; //初始化ICMP的Socket Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Raw, ProtocolType.Icmp); socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.SendTimeout, 1000); // 得到Server EndPoint try { serverHE = Dns.GetHostByName(host); } catch(Exception) { return "没有发现主机"; } // 把 Server IP_EndPoint转换成EndPoint IPEndPoint ipepServer = new IPEndPoint(serverHE.AddressList[0], 0); EndPoint epServer = (ipepServer); // 设定客户机的接收Endpoint fromHE = Dns.GetHostByName(Dns.GetHostName()); IPEndPoint ipEndPointFrom = new IPEndPoint(fromHE.AddressList[0], 0); EndPoint EndPointFrom = (ipEndPointFrom); int PacketSize = 0; IcmpPacket packet = new IcmpPacket(); // 构建要发送的包 packet.Type = ICMP_ECHO; //8 packet.SubCode = 0; packet.CheckSum = UInt16.Parse("0"); packet.Identifier = UInt16.Parse("45"); packet.SequenceNumber = UInt16.Parse("0"); int PingData = 32; // sizeof(IcmpPacket) - 8; packet.Data = new Byte[PingData]; // 初始化Packet.Data for (int i = 0; i < PingData; i++) { packet.Data = (byte)'#'; } //Variable to hold the total Packet size PacketSize = PingData + 8; Byte [] icmp_pkt_buffer = new Byte[ PacketSize ]; Int32 Index = 0; //Call a Method Serialize which counts //The total number of Bytes in the Packet Index = Serialize( packet, icmp_pkt_buffer, PacketSize, PingData ); //Error in Packet Size if( Index == -1 ) { return "Error Creating Packet"; } // convert into a UInt16 array //Get the Half size of the Packet Double double_length = Convert.ToDouble(Index); Double dtemp = Math.Ceiling( double_length / 2); int cksum_buffer_length = Convert.ToInt32(dtemp); //Create a Byte Array UInt16 [] cksum_buffer = new UInt16[cksum_buffer_length]; //Code to initialize the Uint16 array int icmp_header_buffer_index = 0; for( int i = 0; i < cksum_buffer_length; i++ ) { cksum_buffer = BitConverter.ToUInt16(icmp_pkt_buffer,icmp_header_buffer_index); icmp_header_buffer_index += 2; } //Call a method which will return a checksum UInt16 u_cksum = checksum(cksum_buffer, cksum_buffer_length); //Save the checksum to the Packet packet.CheckSum = u_cksum; // Now that we have the checksum, serialize the packet again Byte [] sendbuf = new Byte[ PacketSize ]; //again check the packet size Index = Serialize( packet, sendbuf, PacketSize, PingData ); //if there is a error report it if( Index == -1 ) { return "Error Creating Packet"; } dwStart = System.Environment.TickCount; // Start timing //send the Packet over the socket if ((nBytes = socket.SendTo(sendbuf, PacketSize, 0, epServer)) == SOCKET_ERROR) { return "Socket Error: cannot send Packet"; } // Initialize the buffers. The receive buffer is the size of the // ICMP header plus the IP header (20 bytes) Byte [] ReceiveBuffer = new Byte[256]; nBytes = 0; //Receive the bytes bool recd =false ; int timeout=0 ; //loop for checking the time of the server responding while(!recd) { nBytes = socket.ReceiveFrom(ReceiveBuffer, 256, 0, ref EndPointFrom); if (nBytes == SOCKET_ERROR) { return "主机没有响应" ; } else if(nBytes>0) { dwStop = System.Environment.TickCount - dwStart; // stop timing return "Reply from "+epServer.ToString()+" in " +dwStop+"ms. Received: "+nBytes+ " Bytes."; } timeout=System.Environment.TickCount - dwStart; if(timeout>1000) { return "超时" ; } } //close the socket socket.Close(); return "";}/// <summary>/// This method get the Packet and calculates the total size/// of the Pack by converting it to byte array/// </summary>public static Int32 Serialize(IcmpPacket packet, Byte[] Buffer, Int32 PacketSize, Int32 PingData ){ Int32 cbReturn = 0; // serialize the struct into the array int Index=0; Byte [] b_type = new Byte[1]; b_type[0] = (packet.Type); Byte [] b_code = new Byte[1]; b_code[0] = (packet.SubCode); Byte [] b_cksum = BitConverter.GetBytes(packet.CheckSum); Byte [] b_id = BitConverter.GetBytes(packet.Identifier); Byte [] b_seq = BitConverter.GetBytes(packet.SequenceNumber); Array.Copy( b_type, 0, Buffer, Index, b_type.Length ); Index += b_type.Length; Array.Copy( b_code, 0, Buffer, Index, b_code.Length ); Index += b_code.Length; Array.Copy( b_cksum, 0, Buffer, Index, b_cksum.Length ); Index += b_cksum.Length; Array.Copy( b_id, 0, Buffer, Index, b_id.Length ); Index += b_id.Length; Array.Copy( b_seq, 0, Buffer, Index, b_seq.Length ); Index += b_seq.Length; // copy the data Array.Copy( packet.Data, 0, Buffer, Index, PingData ); Index += PingData; if( Index != PacketSize/* sizeof(IcmpPacket) */) { cbReturn = -1; return cbReturn; } cbReturn = Index; return cbReturn;}/// <summary>/// This Method has the algorithm to make a checksum/// </summary>public static UInt16 checksum( UInt16[] buffer, int size ){ Int32 cksum = 0; int counter; counter = 0; while ( size > 0 ) { UInt16 val = buffer[counter]; cksum += Convert.ToInt32( buffer[counter] ); counter += 1; size -= 1; } cksum = (cksum >> 16) + (cksum & 0xffff); cksum += (cksum >> 16); return (UInt16)(~cksum);}}/// 类结束/// <summary>/// Class that holds the Pack information/// </summary>public class IcmpPacket{public Byte Type; // type of messagepublic Byte SubCode; // type of sub codepublic UInt16 CheckSum; // ones complement checksum of structpublic UInt16 Identifier; // identifierpublic UInt16 SequenceNumber; // sequence numberpublic Byte [] Data;} // class IcmpPacket |
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