C#之WebSocket客户端

效果演示

什么是 WebSocket？

在现代的Web开发中，实时数据传输已成为提升用户体验的重要组成部分。传统的HTTP协议是一个基于请求-响应模式的协议，这意味着客户端每次需要获取新数据时都必须发起一个请求。而对于一些需要实时更新的应用（例如在线聊天、股票行情、实时游戏等），这种方式效率低下且带来了不必要的延迟。

这时，WebSocket应运而生，它为双向通信提供了一个高效、持久的通道。本文将介绍WebSocket的工作原理、应用场景以及如何在Web开发中实现WebSocket。 WebSocket 是一个网络协议，它使得客户端和服务器之间能够建立持久的双向通信通道。与传统的HTTP请求-响应模型不同，WebSocket 连接一旦建立，客户端和服务器之间可以随时相互发送数据，而不需要频繁地建立连接。

WebSocket的特点

1、全双工通信：WebSocket 允许客户端和服务器进行实时的双向通信，不像传统的HTTP协议只能由客户端发起请求。

2、持久连接：WebSocket连接在客户端和服务器之间保持开放，直到显式地关闭连接，这比HTTP的每次请求-响应方式更高效。

3、低延迟：由于是持久连接，WebSocket 可以减少每次请求和响应时的延迟，适合实时更新场景。

4、节省资源：WebSocket 只需要一次握手建立连接，之后的数据交换不需要重新发送HTTP头，减少了网络负担。

使用TouchSocket编写客户端

public class Client
{
	public event GetReceivedEvent OnGetReceivedEvent;

	public event TcpClosedEvent OnTcpClosedEvent;

	public event TcpConnectedEvent OnTcpConnectedEvent;

	public event EventHandler OnLoseLineEvent;

	private Thread pingThread = null;

	private WebSocketClient client = null;

	public bool Online => client.Online;

	private string IPHost = "ws://127.0.0.1:7789/ws";

	private string certificatePath = string.Empty;

	private string password = string.Empty;

	public Client(string IPHost = "ws://127.0.0.1:7789/ws", string certificatePath = "", string password = "")
	{
		this.IPHost = IPHost;
		this.certificatePath = certificatePath;
		this.password = password;
	}

	public async Task Connection(int millisecondsTimeout = 5000)
	{
		try
		{
			client = new WebSocketClient();

			if (!string.IsNullOrEmpty(certificatePath))
			{
				string host = Regex.Match(IPHost, @"//([\d\.]+):").Groups[1].Value;
				await client.SetupAsync(new TouchSocketConfig()
				.SetRemoteIPHost(IPHost)
				.SetClientSslOption(
				new ClientSslOption()
				{
					ClientCertificates = new X509CertificateCollection() { new X509Certificate2(certificatePath, password) },
					SslProtocols = SslProtocols.Tls12,
					TargetHost = host,
					CertificateValidationCallback = (sender, certificate, chain, sslPolicyErrors) => { return true; }
				})
				.ConfigureContainer(a =>
				{
					a.AddConsoleLogger();
				})
				.ConfigurePlugins(a =>
				{
					a.UseTcpReconnection();
					a.UseWebSocketHeartbeat()//使用心跳插件
					.SetTick(TimeSpan.FromSeconds(3));//每1秒ping一次
													  //a.Add<MyWebSocketPlugin>();
				}));
			}
			else
			{
				await client.SetupAsync(new TouchSocketConfig()
				.SetRemoteIPHost(IPHost)
				.ConfigureContainer(a =>
				{
					a.AddConsoleLogger();
				})
				.ConfigurePlugins(a =>
				{
					a.UseTcpReconnection();
					//a.UseWebSocketHeartbeat()//使用心跳插件
					//.SetTick(TimeSpan.FromSeconds(5));//每5秒ping一次
					//								  //a.Add<MyWebSocketPlugin>();
				}));
			}

			client.Received = (c, e) =>
			{
				OnGetReceivedEvent?.Invoke(c, e);
				return e.InvokeNext();
			};

			client.Closed += (c, e) =>
			{

				OnTcpClosedEvent?.Invoke(e);
				return e.InvokeNext();
			};

			await client.ConnectAsync(millisecondsTimeout);
			OnTcpConnectedEvent?.Invoke();
			pingThread = new Thread(() => {
				while (client.Online) 
					Thread.Sleep(1000);
				OnLoseLineEvent?.Invoke("客户端与服务器断开了!",null);
			});
			pingThread.Start();
		}
		catch (Exception ex)
		{
			throw ex;
		}
	}

	public Task SendAsync(WSDataFrame dataFrame, bool endOfMessage = true)
	{
		try
		{
			return client?.SendAsync(dataFrame, endOfMessage);
		}
		catch (Exception ex)
		{
			throw ex;
		}
	}

	public Task SendAsync(string text, bool endOfMessage = true)
	{
		try
		{
			return client?.SendAsync(text, endOfMessage);
		}
		catch (Exception ex)
		{
			throw ex;
		}
	}

	public Task SendAsync(ReadOnlyMemory<byte> memory, bool endOfMessage = true)
	{
		return client?.SendAsync(memory, endOfMessage);
	}

	public async void Close()
	{
		try
		{
			await client?.Client.CloseAsync("主动断开连接");
		}
		catch (Exception ex)
		{
			throw;
		}
	}

	public async void Ping()
	{
		
		try
		{
			await client?.PingAsync();
		}
		catch (Exception ex)
		{
			Console.WriteLine($"{ex.Message}");
		}
	}
}

TouchSocket是一组非常优秀的类库,我是在它的基础上面封装我常用的调用方法！