想着當初到處找不到相關資料來實現.net的Socket通信的痛苦與心酸, 於是將自己寫的代碼公布給大家, 讓大家少走點彎路, 以供參考. 若是覺得文中的思路有哪里不正確的地方, 歡迎大家指正, 共同進步.
說到Socket通信, 必須要有個服務端, 打開一個端口進行監聽(廢話!) 可能大家都會把socket.Accept方法放在一個while(true)的循環里, 當然也沒有錯, 但個人認為這個不科學, 極大可能地占用服務資源. 贊成的請舉手. 所以我想從另外一個方面解決這個問題. 之后是在MSDN找到SocketAsyncEventArgs的一個實例, 然后拿來改改, 有需要的同學可以看看MSDN的官方實例.https://msdn.microsoft.com/en-us/library/system.net.sockets.socketasynceventargs(v=vs.110).aspx
需要了解客戶端寫法的, 請參考: 客戶端實現http://freshflower.iteye.com/blog/2285286
不多說, 接下來貼代碼, 這個實例中需要用到幾個類:
1. BufferManager類, 管理傳輸流的大小 原封不動地拷貝過來,
2. SocketEventPool類: 管理SocketAsyncEventArgs的一個應用池. 有效地重復使用.
3. AsyncUserToken類: 這個可以根據自己的實際情況來定義.主要作用就是存儲客戶端的信息.
4. SocketManager類: 核心,實現Socket監聽,收發信息等操作.
BufferManager類
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Sockets;
using System.Text;
namespace Plates.Service
{
class BufferManager
{
int m_numBytes; // the total number of bytes controlled by the buffer pool
byte[] m_buffer; // the underlying byte array maintained by the Buffer Manager
Stack<int> m_freeIndexPool; //
int m_currentIndex;
int m_bufferSize;
public BufferManager(int totalBytes, int bufferSize)
{
m_numBytes = totalBytes;
m_currentIndex = 0;
m_bufferSize = bufferSize;
m_freeIndexPool = new Stack<int>();
}
// Allocates buffer space used by the buffer pool
public void InitBuffer()
{
// create one big large buffer and divide that
// out to each SocketAsyncEventArg object
m_buffer = new byte[m_numBytes];
}
// Assigns a buffer from the buffer pool to the
// specified SocketAsyncEventArgs object
//
// <returns>true if the buffer was successfully set, else false</returns>
public bool SetBuffer(SocketAsyncEventArgs args)
{
if (m_freeIndexPool.Count > 0)
{
args.SetBuffer(m_buffer, m_freeIndexPool.Pop(), m_bufferSize);
}
else
{
if ((m_numBytes - m_bufferSize) < m_currentIndex)
{
return false;
}
args.SetBuffer(m_buffer, m_currentIndex, m_bufferSize);
m_currentIndex += m_bufferSize;
}
return true;
}
// Removes the buffer from a SocketAsyncEventArg object.
// This frees the buffer back to the buffer pool
public void FreeBuffer(SocketAsyncEventArgs args)
{
m_freeIndexPool.Push(args.Offset);
args.SetBuffer(null, 0, 0);
}
}
}
SocketEventPool類:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Sockets;
using System.Text;
namespace Plates.Service
{
class SocketEventPool
{
Stack<SocketAsyncEventArgs> m_pool;
public SocketEventPool(int capacity)
{
m_pool = new Stack<SocketAsyncEventArgs>(capacity);
}
public void Push(SocketAsyncEventArgs item)
{
if (item == null) { throw new ArgumentNullException("Items added to a SocketAsyncEventArgsPool cannot be null"); }
lock (m_pool)
{
m_pool.Push(item);
}
}
// Removes a SocketAsyncEventArgs instance from the pool
// and returns the object removed from the pool
public SocketAsyncEventArgs Pop()
{
lock (m_pool)
{
return m_pool.Pop();
}
}
// The number of SocketAsyncEventArgs instances in the pool
public int Count
{
get { return m_pool.Count; }
}
public void Clear()
{
m_pool.Clear();
}
}
}
AsyncUserToken類
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
namespace Plates.Service
{
class AsyncUserToken
{
/// <summary>
/// 客戶端IP地址
/// </summary>
public IPAddress IPAddress { get; set; }
/// <summary>
/// 遠程地址
/// </summary>
public EndPoint Remote { get; set; }
/// <summary>
/// 通信SOKET
/// </summary>
public Socket Socket { get; set; }
/// <summary>
/// 連接時間
/// </summary>
public DateTime ConnectTime { get; set; }
/// <summary>
/// 所屬用戶信息
/// </summary>
public UserInfoModel UserInfo { get; set; }
/// <summary>
/// 數據緩存區
/// </summary>
public List<byte> Buffer { get; set; }
public AsyncUserToken()
{
this.Buffer = new List<byte>();
}
}
}
SocketManager類
using Plates.Common;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
namespace Plates.Service
{
class SocketManager
{
private int m_maxConnectNum; //最大連接數
private int m_revBufferSize; //最大接收字節數
BufferManager m_bufferManager;
const int opsToAlloc = 2;
Socket listenSocket; //監聽Socket
SocketEventPool m_pool;
int m_clientCount; //連接的客戶端數量
Semaphore m_maxNumberAcceptedClients;
List<AsyncUserToken> m_clients; //客戶端列表
#region 定義委托
/// <summary>
/// 客戶端連接數量變化時觸發
/// </summary>
/// <param name="num">當前增加客戶的個數(用戶退出時為負數,增加時為正數,一般為1)</param>
/// <param name="token">增加用戶的信息</param>
public delegate void OnClientNumberChange(int num, AsyncUserToken token);
/// <summary>
/// 接收到客戶端的數據
/// </summary>
/// <param name="token">客戶端</param>
/// <param name="buff">客戶端數據</param>
public delegate void OnReceiveData(AsyncUserToken token, byte[] buff);
#endregion
#region 定義事件
/// <summary>
/// 客戶端連接數量變化事件
/// </summary>
public event OnClientNumberChange ClientNumberChange;
/// <summary>
/// 接收到客戶端的數據事件
/// </summary>
public event OnReceiveData ReceiveClientData;
#endregion
#region 定義屬性
/// <summary>
/// 獲取客戶端列表
/// </summary>
public List<AsyncUserToken> ClientList { get { return m_clients; } }
#endregion
/// <summary>
/// 構造函數
/// </summary>
/// <param name="numConnections">最大連接數</param>
/// <param name="receiveBufferSize">緩存區大小</param>
public SocketManager(int numConnections, int receiveBufferSize)
{
m_clientCount = 0;
m_maxConnectNum = numConnections;
m_revBufferSize = receiveBufferSize;
// allocate buffers such that the maximum number of sockets can have one outstanding read and
//write posted to the socket simultaneously
m_bufferManager = new BufferManager(receiveBufferSize * numConnections * opsToAlloc, receiveBufferSize);
m_pool = new SocketEventPool(numConnections);
m_maxNumberAcceptedClients = new Semaphore(numConnections, numConnections);
}
/// <summary>
/// 初始化
/// </summary>
public void Init()
{
// Allocates one large byte buffer which all I/O operations use a piece of. This gaurds
// against memory fragmentation
m_bufferManager.InitBuffer();
m_clients = new List<AsyncUserToken>();
// preallocate pool of SocketAsyncEventArgs objects
SocketAsyncEventArgs readWriteEventArg;
for (int i = 0; i < m_maxConnectNum; i++)
{
readWriteEventArg = new SocketAsyncEventArgs();
readWriteEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(IO_Completed);
readWriteEventArg.UserToken = new AsyncUserToken();
// assign a byte buffer from the buffer pool to the SocketAsyncEventArg object
m_bufferManager.SetBuffer(readWriteEventArg);
// add SocketAsyncEventArg to the pool
m_pool.Push(readWriteEventArg);
}
}
/// <summary>
/// 啟動服務
/// </summary>
/// <param name="localEndPoint"></param>
public bool Start(IPEndPoint localEndPoint)
{
try
{
m_clients.Clear();
listenSocket = new Socket(localEndPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
listenSocket.Bind(localEndPoint);
// start the server with a listen backlog of 100 connections
listenSocket.Listen(m_maxConnectNum);
// post accepts on the listening socket
StartAccept(null);
return true;
}
catch (Exception)
{
return false;
}
}
/// <summary>
/// 停止服務
/// </summary>
public void Stop()
{
foreach (AsyncUserToken token in m_clients)
{
try
{
token.Socket.Shutdown(SocketShutdown.Both);
}
catch (Exception) { }
}
try
{
listenSocket.Shutdown(SocketShutdown.Both);
}
catch (Exception) { }
listenSocket.Close();
int c_count = m_clients.Count;
lock (m_clients) { m_clients.Clear(); }
if (ClientNumberChange != null)
ClientNumberChange(-c_count, null);
}
public void CloseClient(AsyncUserToken token)
{
try
{
token.Socket.Shutdown(SocketShutdown.Both);
}
catch (Exception) { }
}
// Begins an operation to accept a connection request from the client
//
// <param name="acceptEventArg">The context object to use when issuing
// the accept operation on the server's listening socket</param>
public void StartAccept(SocketAsyncEventArgs acceptEventArg)
{
if (acceptEventArg == null)
{
acceptEventArg = new SocketAsyncEventArgs();
acceptEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(AcceptEventArg_Completed);
}
else
{
// socket must be cleared since the context object is being reused
acceptEventArg.AcceptSocket = null;
}
m_maxNumberAcceptedClients.WaitOne();
if (!listenSocket.AcceptAsync(acceptEventArg))
{
ProcessAccept(acceptEventArg);
}
}
// This method is the callback method associated with Socket.AcceptAsync
// operations and is invoked when an accept operation is complete
//
void AcceptEventArg_Completed(object sender, SocketAsyncEventArgs e)
{
ProcessAccept(e);
}
private void ProcessAccept(SocketAsyncEventArgs e)
{
try
{
Interlocked.Increment(ref m_clientCount);
// Get the socket for the accepted client connection and put it into the
//ReadEventArg object user token
SocketAsyncEventArgs readEventArgs = m_pool.Pop();
AsyncUserToken userToken = (AsyncUserToken)readEventArgs.UserToken;
userToken.Socket = e.AcceptSocket;
userToken.ConnectTime = DateTime.Now;
userToken.Remote = e.AcceptSocket.RemoteEndPoint;
userToken.IPAddress = ((IPEndPoint)(e.AcceptSocket.RemoteEndPoint)).Address;
lock (m_clients) { m_clients.Add(userToken); }
if (ClientNumberChange != null)
ClientNumberChange(1, userToken);
if (!e.AcceptSocket.ReceiveAsync(readEventArgs))
{
ProcessReceive(readEventArgs);
}
}
catch (Exception me)
{
RuncomLib.Log.LogUtils.Info(me.Message + "\r\n" + me.StackTrace);
}
// Accept the next connection request
if (e.SocketError == SocketError.OperationAborted) return;
StartAccept(e);
}
void IO_Completed(object sender, SocketAsyncEventArgs e)
{
// determine which type of operation just completed and call the associated handler
switch (e.LastOperation)
{
case SocketAsyncOperation.Receive:
ProcessReceive(e);
break;
case SocketAsyncOperation.Send:
ProcessSend(e);
break;
default:
throw new ArgumentException("The last operation completed on the socket was not a receive or send");
}
}
// This method is invoked when an asynchronous receive operation completes.
// If the remote host closed the connection, then the socket is closed.
// If data was received then the data is echoed back to the client.
//
private void ProcessReceive(SocketAsyncEventArgs e)
{
try
{
// check if the remote host closed the connection
AsyncUserToken token = (AsyncUserToken)e.UserToken;
if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success)
{
//讀取數據
byte[] data = new byte[e.BytesTransferred];
Array.Copy(e.Buffer, e.Offset, data, 0, e.BytesTransferred);
lock (token.Buffer)
{
token.Buffer.AddRange(data);
}
//注意:你一定會問,這里為什么要用do-while循環?
//如果當客戶發送大數據流的時候,e.BytesTransferred的大小就會比客戶端發送過來的要小,
//需要分多次接收.所以收到包的時候,先判斷包頭的大小.夠一個完整的包再處理.
//如果客戶短時間內發送多個小數據包時, 服務器可能會一次性把他們全收了.
//這樣如果沒有一個循環來控制,那么只會處理第一個包,
//剩下的包全部留在token.Buffer中了,只有等下一個數據包過來后,才會放出一個來.
do
{
//判斷包的長度
byte[] lenBytes = token.Buffer.GetRange(0, 4).ToArray();
int packageLen = BitConverter.ToInt32(lenBytes, 0);
if (packageLen > token.Buffer.Count - 4)
{ //長度不夠時,退出循環,讓程序繼續接收
break;
}
//包夠長時,則提取出來,交給后面的程序去處理
byte[] rev = token.Buffer.GetRange(4, packageLen).ToArray();
//從數據池中移除這組數據
lock (token.Buffer)
{
token.Buffer.RemoveRange(0, packageLen + 4);
}
//將數據包交給后台處理,這里你也可以新開個線程來處理.加快速度.
if(ReceiveClientData != null)
ReceiveClientData(token, rev);
//這里API處理完后,並沒有返回結果,當然結果是要返回的,卻不是在這里, 這里的代碼只管接收.
//若要返回結果,可在API處理中調用此類對象的SendMessage方法,統一打包發送.不要被微軟的示例給迷惑了.
} while (token.Buffer.Count > 4);
//繼續接收. 為什么要這么寫,請看Socket.ReceiveAsync方法的說明
if (!token.Socket.ReceiveAsync(e))
this.ProcessReceive(e);
}
else
{
CloseClientSocket(e);
}
}
catch (Exception xe)
{
RuncomLib.Log.LogUtils.Info(xe.Message + "\r\n" + xe.StackTrace);
}
}
// This method is invoked when an asynchronous send operation completes.
// The method issues another receive on the socket to read any additional
// data sent from the client
//
// <param name="e"></param>
private void ProcessSend(SocketAsyncEventArgs e)
{
if (e.SocketError == SocketError.Success)
{
// done echoing data back to the client
AsyncUserToken token = (AsyncUserToken)e.UserToken;
// read the next block of data send from the client
bool willRaiseEvent = token.Socket.ReceiveAsync(e);
if (!willRaiseEvent)
{
ProcessReceive(e);
}
}
else
{
CloseClientSocket(e);
}
}
//關閉客戶端
private void CloseClientSocket(SocketAsyncEventArgs e)
{
AsyncUserToken token = e.UserToken as AsyncUserToken;
lock (m_clients) { m_clients.Remove(token); }
//如果有事件,則調用事件,發送客戶端數量變化通知
if (ClientNumberChange != null)
ClientNumberChange(-1, token);
// close the socket associated with the client
try
{
token.Socket.Shutdown(SocketShutdown.Send);
}
catch (Exception) { }
token.Socket.Close();
// decrement the counter keeping track of the total number of clients connected to the server
Interlocked.Decrement(ref m_clientCount);
m_maxNumberAcceptedClients.Release();
// Free the SocketAsyncEventArg so they can be reused by another client
e.UserToken = new AsyncUserToken();
m_pool.Push(e);
}
/// <summary>
/// 對數據進行打包,然后再發送
/// </summary>
/// <param name="token"></param>
/// <param name="message"></param>
/// <returns></returns>
public void SendMessage(AsyncUserToken token, byte[] message)
{
if (token == null || token.Socket == null || !token.Socket.Connected)
return;
try
{
//對要發送的消息,制定簡單協議,頭4字節指定包的大小,方便客戶端接收(協議可以自己定)
byte[] buff = new byte[message.Length + 4];
byte[] len = BitConverter.GetBytes(message.Length);
Array.Copy(len, buff, 4);
Array.Copy(message, 0, buff, 4, message.Length);
//token.Socket.Send(buff); //這句也可以發送, 可根據自己的需要來選擇
//新建異步發送對象, 發送消息
SocketAsyncEventArgs sendArg = new SocketAsyncEventArgs();
sendArg.UserToken = token;
sendArg.SetBuffer(buff, 0, buff.Length); //將數據放置進去.
token.Socket.SendAsync(sendArg);
}
catch (Exception e){
RuncomLib.Log.LogUtils.Info("SendMessage - Error:" + e.Message);
}
}
}
}
調用方法:
SocketManager m_socket = new SocketManager(200, 1024);
m_socket.Init();
m_socket.Start(new IPEndPoint(IPAddress.Any, 13909));
好了,大功告成, 當初自己在寫這些代碼的時候, 一個地方就卡上很久, 燒香拜菩薩都沒有用, 只能憑網上零星的一點代碼給點提示. 現在算是做個總結吧. 讓大家一看就明白, Socket通信就是這樣, 可簡單可復雜.
上面說的是服務器,那客戶端的請參考
C#如何利用SocketAsyncEventArgs實現高效能TCPSocket通信 (客戶端實現)
注: 本貼為原創貼, 轉載請注明出處: http://freshflower.iteye.com/blog/2285272