C#利用服务器实现客户端之间通信

时间:2022-04-07 04:36:34

这两天在学习C#,C#高级编程真的是厚厚的一本书QAQ。

昨天看了一下里面的通信部分(其实还没怎么看),看了网上一些人的博客,自己在他们的博客基础上写了一个通信。

先来讲述下我自己对于整个Socket通信过程的理解,毕竟初学,说错见谅,知道错了会改正~

首先在服务端新建一个serverSocket,对其进行初始化(一般包含AddressFamily:IP地址类型,SocketType:Socket传输数据方式,ProtoType:传输协议);

接着我们要设置server端要绑定的IP:port;然后开始监听,并设置最多同时监听多少个Client.

这时,服务端就在等待状态,直到某一个Client连接到这个ip:port上,这时serverSocket.Accept()工作,获得这个连接。(此时的连接是有地址信息的哦!记得保存)

获得连接之后,server就可以和这个Client进行通信了,当加入第二个Client(我们称其为ClientB)时,Server接收到ClientB的消息,可以将这个消息转发给前一个Client(我们称其为ClientA),当受到ClientA的消息,也可以转发给ClientB。这样就实现了Clients之间的通信了。(重点在保存连接信息!!

那么现在贴上代码讲解:

Server端代码

 namespace SocketServer
{
class Program
{
private static byte[] result = new byte[]; static Socket serverSocket;
private static string client;
private static Socket clientSocket;
//我这里存了两个Client,因为自己电脑开了两个Client,不会有多的
//理论上应该开一个Socket[]来保存信息,最好用一个二元组将client的信息和连接绑定起来
//这样就可以实现断开连接后下次登陆还是可以识别是这个Client
private static Socket clientSocketA=null;
private static Socket clientSocketB=null; static void Main(string[] args)
{
Program.SetPort();
}
private static void SetPort(int port)
{
IPAddress ip = IPAddress.Parse("127.0.0.1");//set ip
serverSocket = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp);//initialize
serverSocket.Bind(new IPEndPoint(ip, port));//bind
serverSocket.Listen();
//进入监听状态
Console.WriteLine("监听{0}成功", serverSocket.LocalEndPoint.ToString());
//开启一个线程来监听客户端连接
Thread myThread = new Thread(ListenClientConnect);
myThread.Start();
Console.ReadLine(); }
/// <summary>
/// 监听客户端连接
/// </summary>
private static void ListenClientConnect()
{
while (true)
{
//Client连接上后 得到这个连接
clientSocket = serverSocket.Accept(); //这里我因为只有两个Client,所以就简单写了
if (clientSocketA == null)
{
clientSocketA = clientSocket;
}
else if (clientSocketB == null)
{
clientSocketB = clientSocket;
}
else
{
//当其中一个断开了,又重新连接时,需要再次保存连接
if (clientSocketB.IsBound)
{
clientSocketA = clientSocketB;
clientSocketB = clientSocket;
}
else
{
clientSocketB = clientSocketA;
clientSocketA = clientSocket;
} }
clientSocket.Send(Encoding.ASCII.GetBytes("say hello"));
//开个线程接收Client信息
Thread receivedThread = new Thread(ReceiveMessage);
receivedThread.Start(clientSocket); }
} private static void ReceiveMessage(object clientSocket)
{
Socket myClientSocket = (Socket) clientSocket; while (true)
{
try
{
int revceiveNumber = myClientSocket.Receive(result);
//Console.WriteLine("接受客户端{0}消息{1}", myClientSocket.RemoteEndPoint.ToString()
// , Encoding.ASCII.GetString(result, 0, revceiveNumber));
Console.WriteLine(Encoding.ASCII.GetString(result, , revceiveNumber));
if (myClientSocket == clientSocketA)
{
Console.WriteLine("receive from A");
if (clientSocketB!=null&&clientSocketB.IsBound)
{
Console.WriteLine("a IS BOUND");
clientSocketB.Send(result, , revceiveNumber, SocketFlags.None);
}
else
{
myClientSocket.Send(Encoding.ASCII.GetBytes("the people is not online! Send Failed!"));
Console.WriteLine("对方不在线上,发送失败!");
}
}
else
{
Console.WriteLine("receive from B");
if (clientSocketA != null && clientSocketA.IsBound)
{
Console.WriteLine("a IS BOUND");
clientSocketA.Send(result, , revceiveNumber, SocketFlags.None);
}
else
{
myClientSocket.Send(Encoding.ASCII.GetBytes("the people is not online! Send Failed!"));
Console.WriteLine("对方不在线上,发送失败!");
} } }
catch(Exception ex)
{
Console.WriteLine(ex.Message);
myClientSocket.Shutdown(SocketShutdown.Both);
myClientSocket.Close();
break; }
} }
}
}

Client端代码(因为都差不多 就只贴一个了)

 namespace SocketClient
{
class Program
{
private static byte[] result = new byte[];
private static Socket clientSocket;
private static void ListenServer()
{
while (true)
{
result = new byte[];
int receiveLength = clientSocket.Receive(result); Console.WriteLine("{0}", Encoding.ASCII.GetString(result, , receiveLength));
} }
static void Main(string[] args)
{ IPAddress ip = IPAddress.Parse("127.0.0.1");
clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
try
{
clientSocket.Connect(ip, );
Console.WriteLine("连接成功!"); }
catch (Exception e)
{
Console.WriteLine("连接失败!");
return;
}
Thread threadRead = new Thread(ListenServer);
threadRead.Start(); while(true)
{
try
{
Thread.Sleep();
string sendMessage = Console.ReadLine();
clientSocket.Send(Encoding.ASCII.GetBytes("Sylvia:"+sendMessage)); }
catch (Exception ex)
{
clientSocket.Shutdown(SocketShutdown.Both);
clientSocket.Close();
break;
} }
Console.WriteLine("发送完毕 按回车退出");
Console.ReadKey();
}
}
}

写的时候要特别注意一下Send信息的时候,注意byte[]的传输大小,很容易变成byte[]数组的大小而不是内容的大小。

这个大家就自己尝试吧