C# Socket编程

服务端（server side）

sing System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;

namespace MyChatServer
{

internal class server
{
[STAThread]
private static void Main(string[] args)
{
int recv;
byte[] data = new byte[1024];
IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, 9050);
Socket newSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
newSocket.Bind(ipEnd);
newSocket.Listen(10);
Console.WriteLine("Waiting for a client...");
Socket client = newSocket.Accept();
IPEndPoint clientIp = client.RemoteEndPoint as IPEndPoint;
Console.WriteLine("connect with client: " + clientIp.Address + " at port; " + clientIp.Port);

string welcome = "welcome here";
data = Encoding.ASCII.GetBytes(welcome);
client.Send(data, data.Length, SocketFlags.None);

while (true)
{
data = new byte[1024];
recv = client.Receive(data);
Console.WriteLine("recv = " + recv);

if (recv == 0)
{
break;
}

Console.WriteLine(Encoding.ASCII.GetString(data, 0, recv));
client.Send(data, recv, SocketFlags.None);
}

Console.WriteLine("Disconnected from " + clientIp.Address);
client.Close();
newSocket.Close();
}
}
}

客户端（Client Side）

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

namespace tcpclient
{
/// <summary>
/// Class1 的摘要说明。
/// </summary>
class client
{
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main(string[] args)
{
//
// TODO: 在此处添加代码以启动应用程序
//
byte[] data=new byte[1024];
Socket newclient=new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
Console.Write("please input the server ip:");
string ipadd=Console.ReadLine();
Console.WriteLine();
Console.Write("please input the server port:");
int port=Convert.ToInt32(Console.ReadLine());
IPEndPoint ie=new IPEndPoint(IPAddress.Parse(ipadd),port);//服务器的IP和端口
try
{
//因为客户端只是用来向特定的服务器发送信息，所以不需要绑定本机的IP和端口。不需要监听。
newclient.Connect(ie);
}
catch(SocketException e)
{
Console.WriteLine("unable to connect to server");
Console.WriteLine(e.ToString());
return;
}
int recv = newclient.Receive(data);
string stringdata=Encoding.ASCII.GetString(data,0,recv);
Console.WriteLine(stringdata);
while(true)
{
string input=Console.ReadLine();
if(input=="exit")
break;
newclient.Send(Encoding.ASCII.GetBytes(input));
data=new byte[1024];
recv=newclient.Receive(data);
stringdata=Encoding.ASCII.GetString(data,0,recv);
Console.WriteLine(stringdata);
}
Console.WriteLine("disconnect from sercer");
newclient.Shutdown(SocketShutdown.Both);
newclient.Close();

}
}
}

如果要在Unity中在web platform使用Socket编程（Window平台），需要做以下操作：

1、首先找到sockpol.exe文件。文件路径..\Unity\Editor\Data\Tools\SocketPolicyServer\sockpol.exe

2、然后打开cmd控制台，并且进入到sockpol.exe目录，打开sockpol服务，服务不能关闭。在cmd中使用netstat -ano命令可以看到一个843端口的服务。



3、在客户端连接（Unity中）的开始部分，加上下面这句代码。

Security.PrefetchSocketPolicy(ipAddress, 843); //端口号843固定，ipAddress为服务器的ip