using System;
using System.Collections;
using System.Data;
using System.Net.Sockets;
using System.Net;
///  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.WriteLine(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[i] = (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[i] =
    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 message
 public Byte  SubCode;    // type of sub code
 public UInt16 CheckSum;   // ones complement checksum of struct
 public UInt16 Identifier;      // identifier
 public UInt16 SequenceNumber;     // sequence number
 public Byte [] Data;
} // class IcmpPacket



 
											





 
	    

 
	
 
											



