本篇文章主要介紹了.NET實現即時通信，WebSocket服務端實例 ，小編覺得挺不錯的，現在分享給大家，也給大家做個參考。一起跟著小編過來看看吧
即時通訊常用手段
#1.第三方平台谷歌、騰訊環信等多如牛毛，其中谷歌即時通訊是免費的，但免費就是免費的並不好用。其他的一些第三方一般收費的，使用要則限流（1s/限制x條訊息）要么則限制用戶數。
但穩定性什麼都還不錯，又能將服務壓力甩出
2.System.Net.Sockets.Socket，也能寫一套較好的伺服器端。在.NET 4.5之前用較多，使用起來很麻煩。需要對資料包進行解析等操作（但看似網路上有對超長包的處理方法）
3.System.Net.WebSockets.WebSocket，這個，是.NET 4.5出來的東西，對伺服器環境也有所要求，IIS8以上。意味著Windows Server2008R2自帶的IIS不支持，Windows8及Server2012以上自備的IIS可以。本文主要將此方式的實例
完整流程
#1).用戶端請求連線
程式碼如下:
ws = new WebSocket('ws://' + window.location.hostname + ':' + window.location.port + '/Handler1.ashx?user=' + $("#user" ).val());
2).服務端取得連線物件並儲存到連線池中
CONNECT_POOL.Add(user, socket);
3).連線物件開始監聽（每個客戶端與伺服器保存長連結）
程式碼如下:
WebSocketReceiveResult result = await socket.ReceiveAsync(buffer, CancellationToken.None);
4).客戶端A發送訊息給B
ws.send($("#to").val() + "|" + $('#content').val());string userMsg = Encoding.UTF8.GetString(buffer.Array, 0, result.Count);
WebSocket destSocket = CONNECT_POOL[descUser]; await destSocket.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
WebSocketReceiveResult result = await socket.ReceiveAsync(buffer, CancellationToken.None);
ws.onmessage = function (evt) {
$('#msg').append('<p>' + evt.data + '</p>');
}<script> var ws; $().ready(function () { $('#conn').click(function () { ws = new WebSocket('ws://' + window.location.hostname + ':' + window.location.port + '/Handler1.ashx?user=' + $("#user").val()); $('#msg').append('<p>正在连接</p>'); ws.onopen = function () { $('#msg').append('<p>已经连接</p>'); } ws.onmessage = function (evt) { $('#msg').append('<p>' + evt.data + '</p>'); } ws.onerror = function (evt) { $('#msg').append('<p>' + JSON.stringify(evt) + '</p>'); } ws.onclose = function () { $('#msg').append('<p>已经关闭</p>'); } }); $('#close').click(function () { ws.close(); }); $('#send').click(function () { if (ws.readyState == WebSocket.OPEN) { ws.send($("#to").val() + "|" + $(&#39;#content&#39;).val()); } else { $('#tips').text('连接已经关闭'); } }); }); </script>
目的用户
using System;
using System.Collections;
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 WebApplication1
{
/// <summary>
/// 离线消息
/// </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 的摘要说明
/// </summary>
public class Handler1 : IHttpHandler
{
private static Dictionary<string, WebSocket> CONNECT_POOL = new Dictionary<string, WebSocket>();//用户连接池
private static Dictionary<string, List<MessageInfo>> MESSAGE_POOL = new Dictionary<string, List<MessageInfo>>();//离线消息池
public void ProcessRequest(HttpContext context)
{
if (context.IsWebSocketRequest)
{
context.AcceptWebSocketRequest(ProcessChat);
}
}
private async Task ProcessChat(AspNetWebSocketContext context)
{
WebSocket socket = context.WebSocket;
string user = context.QueryString["user"].ToString();
try
{
#region 用户添加连接池
//第一次open时，添加到连接池中
if (!CONNECT_POOL.ContainsKey(user))
CONNECT_POOL.Add(user, socket);//不存在，添加
else
if (socket != CONNECT_POOL[user])//当前对象不一致，更新
CONNECT_POOL[user] = socket;
#endregion
#region 离线消息处理
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);//移除离线消息
}
#endregion
string descUser = string.Empty;//目的用户
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 消息处理（字符截取、消息转发）
try
{
#region 关闭Socket处理，删除连接池
if (socket.State != WebSocketState.Open)//连接关闭
{
if (CONNECT_POOL.ContainsKey(user)) CONNECT_POOL.Remove(user);//删除连接池
break;
}
#endregion
string userMsg = Encoding.UTF8.GetString(buffer.Array, 0, result.Count);//发送过来的消息
string[] msgList = userMsg.Split('|');
if (msgList.Length == 2)
{
if (msgList[0].Trim().Length > 0)
descUser = msgList[0].Trim();//记录消息目的用户
buffer = new ArraySegment<byte>(Encoding.UTF8.GetBytes(msgList[1]));
}
else
buffer = new ArraySegment<byte>(Encoding.UTF8.GetBytes(userMsg));
if (CONNECT_POOL.ContainsKey(descUser))//判断客户端是否在线
{
WebSocket destSocket = CONNECT_POOL[descUser];//目的客户端
if (destSocket != null && destSocket.State == WebSocketState.Open)
await destSocket.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
}
else
{
Task.Run(() =>
{
if (!MESSAGE_POOL.ContainsKey(descUser))//将用户添加至离线消息池中
MESSAGE_POOL.Add(descUser, new List<MessageInfo>());
MESSAGE_POOL[descUser].Add(new MessageInfo(DateTime.Now, buffer));//添加离线消息
});
}
}
catch (Exception exs)
{
//消息转发异常处理，本次消息忽略 继续监听接下来的消息
}
#endregion
}
else
{
break;
}
}//while end
}
catch (Exception ex)
{
//整体异常处理
if (CONNECT_POOL.ContainsKey(user)) CONNECT_POOL.Remove(user);
}
}
public bool IsReusable
{
get
{
return false;
}
}
}
}以上是.NET實作WebSocket服務端即時通訊的實例詳解的詳細內容。更多資訊請關注PHP中文網其他相關文章！
