服務器端代碼編寫
1.新建一個ASP.net Web MVC5項目
2.新建一個“一般處理程序”

3.Handler1.ashx代碼如下:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.WebSockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Web;
using System.Web.WebSockets;
namespace WebApplicationWebsocketHandler
{
/// <summary>
/// 離線消息
/// </summary>
public class MessageInfo
{
public MessageInfo(DateTime _MsgTime, ArraySegment<byte> _MsgContent)
{
MsgTime = _MsgTime;
MsgContent = _MsgContent;
}
public DateTime MsgTime { get; set; }
public ArraySegment<byte> MsgContent { get; set; }
}
/// <summary>
/// Handler1 的摘要說明
/// </summary>
public class Handler1 : IHttpHandler
{
private static Dictionary<string, WebSocket> CONNECT_POOL = new Dictionary<string, WebSocket>();//用戶連接池
private static Dictionary<string, List<MessageInfo>> MESSAGE_POOL = new Dictionary<string, List<MessageInfo>>();//離線消息池
public void ProcessRequest(HttpContext context)
{
//context.Response.ContentType = "text/plain";
//context.Response.Write("Hello World");
if (context.IsWebSocketRequest)
{
context.AcceptWebSocketRequest(ProcessChat);
}
}
private async Task ProcessChat(AspNetWebSocketContext context)
{
WebSocket socket = context.WebSocket;
string user = context.QueryString["user"].ToString();
try
{
#region 用戶添加連接池
//第一次open時,添加到連接池中
if (!CONNECT_POOL.ContainsKey(user))
CONNECT_POOL.Add(user, socket);//不存在,添加
else
if (socket != CONNECT_POOL[user])//當前對象不一致,更新
CONNECT_POOL[user] = socket;
#endregion
#region 離線消息處理
if (MESSAGE_POOL.ContainsKey(user))
{
List<MessageInfo> msgs = MESSAGE_POOL[user];
foreach (MessageInfo item in msgs)
{
await socket.SendAsync(item.MsgContent, WebSocketMessageType.Text, true, CancellationToken.None);
}
MESSAGE_POOL.Remove(user);//移除離線消息
}
#endregion
string descUser = string.Empty;//目的用戶
while (true)
{
if (socket.State == WebSocketState.Open)
{
ArraySegment<byte> buffer = new ArraySegment<byte>(new byte[2048]);
WebSocketReceiveResult result = await socket.ReceiveAsync(buffer, CancellationToken.None);
#region 消息處理(字符截取、消息轉發)
try
{
#region 關閉Socket處理,刪除連接池
if (socket.State != WebSocketState.Open)//連接關閉
{
if (CONNECT_POOL.ContainsKey(user)) CONNECT_POOL.Remove(user);//刪除連接池
break;
}
#endregion
string userMsg = Encoding.UTF8.GetString(buffer.Array, 0, result.Count);//發送過來的消息
string[] msgList = userMsg.Split('|');
if (msgList.Length == 2)
{
if (msgList[0].Trim().Length > 0)
descUser = msgList[0].Trim();//記錄消息目的用戶
buffer = new ArraySegment<byte>(Encoding.UTF8.GetBytes(msgList[1]));
}
else
buffer = new ArraySegment<byte>(Encoding.UTF8.GetBytes(userMsg));
if (CONNECT_POOL.ContainsKey(descUser))//判斷客戶端是否在線
{
WebSocket destSocket = CONNECT_POOL[descUser];//目的客戶端
if (destSocket != null && destSocket.State == WebSocketState.Open)
await destSocket.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
}
else
{
Task.Run(() =>
{
if (!MESSAGE_POOL.ContainsKey(descUser))//將用戶添加至離線消息池中
MESSAGE_POOL.Add(descUser, new List<MessageInfo>());
MESSAGE_POOL[descUser].Add(new MessageInfo(DateTime.Now, buffer));//添加離線消息
});
}
}
catch (Exception exs)
{
//消息轉發異常處理,本次消息忽略 繼續監聽接下來的消息
}
#endregion
}
else
{
break;
}
}//while end
}
catch (Exception ex)
{
//整體異常處理
if (CONNECT_POOL.ContainsKey(user)) CONNECT_POOL.Remove(user);
}
}
public bool IsReusable
{
get
{
return false;
}
}
}
}
4.運行看是否報錯,若沒錯將我們的服務器網站發布到IIS(支持WebSocket的IIS上,win7的系統時不可以的)上
點擊“生成”->"發布........",以文件系統的方式發布,目標位置為我們創建的IIS網站對應的物理路徑

