vue3.0 + SignalR（vue客户端 + net core3.0服务端）

一、 net core3.0服务端搭建

　　1. 创建core的web应用程序，项目建好之后右键项目->添加>客户端库。

　　

 　　2. 把Pages下面的Index视图的代码换成如下：

@page
<div class="container">
    <div class="row">&nbsp;</div>
    <div class="row">
        <div class="col-2">User</div>
        <div class="col-4"><input type="text" id="userInput" /></div>
    </div>
    <div class="row">
        <div class="col-2">Message</div>
        <div class="col-4"><input type="text" id="messageInput" /></div>
    </div>
    <div class="row">&nbsp;</div>
    <div class="row">
        <div class="col-6">
            <input type="button" id="sendButton" value="Send Message" />
        </div>
    </div>
</div>
<div class="row">
    <div class="col-12">
        <hr />
    </div>
</div>
<div class="row">
    <div class="col-6">
        <ul id="messagesList"></ul>
    </div>
</div>
<script src="~/js/signalr/dist/browser/signalr.js"></script>
<script src="~/js/chat.js"></script>

　　3. 在放静态文件的wwwroot的js下面新建一个chat.js，并放入如下代码：

"use strict";

var connection = new signalR.HubConnectionBuilder().withUrl("/chatHub").build();

//Disable send button until connection is established
document.getElementById("sendButton").disabled = true;

connection.on("ReceiveMessage", function (user, message) {
    var msg = message.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
    var encodedMsg = user + " says " + msg;
    var li = document.createElement("li");
    li.textContent = encodedMsg;
    document.getElementById("messagesList").appendChild(li);
});

connection.start().then(function () {
    document.getElementById("sendButton").disabled = false;
}).catch(function (err) {
    return console.error(err.toString());
});

document.getElementById("sendButton").addEventListener("click", function (event) {
    var user = document.getElementById("userInput").value;
    var message = document.getElementById("messageInput").value;
    connection.invoke("SendMessage", user, message).catch(function (err) {
        return console.error(err.toString());
    });
    event.preventDefault();
});

　　4. 项目根目录添加Hubs文件夹，加个ChatHub类：

"use strict";

var connection = new signalR.HubConnectionBuilder().withUrl("/chatHub").build();

//Disable send button until connection is established
document.getElementById("sendButton").disabled = true;

connection.on("ReceiveMessage", function (user, message) {
    var msg = message.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
    var encodedMsg = user + " says " + msg;
    var li = document.createElement("li");
    li.textContent = encodedMsg;
    document.getElementById("messagesList").appendChild(li);
});

connection.start().then(function () {
    document.getElementById("sendButton").disabled = false;
}).catch(function (err) {
    return console.error(err.toString());
});

document.getElementById("sendButton").addEventListener("click", function (event) {
    var user = document.getElementById("userInput").value;
    var message = document.getElementById("messageInput").value;
    connection.invoke("SendMessage", user, message).catch(function (err) {
        return console.error(err.toString());
    });
    event.preventDefault();
});

　　5. 在Startup里配置SignalR - ConfigureServices里加上 

services.AddSignalR();

　　6. 在Startup里配置SignalR - Configure里加上

app.UseEndpoints(endpoints =>
            {
                endpoints.MapRazorPages();
                endpoints.MapHub<ChatHub>("/chathub");
            });

　　7. 至此，服务端已经搭建完成，可运行看下效果，效果如下：

　　

 

二、vue3.0 客户端搭建

　　1. 安装signalr前端客户端包：

npm install @aspnet/signalr

　　2. 项目新建测试文件 SignalR.vue 文件内容如下

<template>
  <div class="home">
    <h1>前端演示SignalR</h1>
    <input v-model="user" type="text" />
    <input v-model="message" type="text" />
    <button @click="sendAll">发送全部</button>
    <button @click="sendOwn">对自己发送</button>
    <div>
      <ul v-for="(item ,index) in messages" v-bind:key="index +'itemMessage'">
        <li>{{item.user}} says {{item.message}}</li>
      </ul>
    </div>
  </div>
</template>

<script>
import * as signalR from "@aspnet/signalr";
export default {
  name: "SignalR",
  components: {},
  data() {
    return {
      user: "", //用户
      message: "", //消息
      connection: "", //signalr连接
      messages: [] //返回消息
    };
  },
  methods: {
    //给全部发送消息
    sendAll: function() {
      this.connection
        .invoke("SendMessage", this.user, this.message)
        .catch(function(err) {
          return console.error(err);
        });
    },
    //只给自己发送消息
    sendOwn: function() {
      this.connection
        .invoke("SendMessageCaller", this.message)
        .catch(function(err) {
          return console.error(err);
        });
    }

 
  },
  created: function() {
    let thisVue = this;
    this.connection = new signalR.HubConnectionBuilder()
      .withUrl("http://localhost:13989/chathub", {
        skipNegotiation: true,
        transport: signalR.HttpTransportType.WebSockets
      })
      .configureLogging(signalR.LogLevel.Information)
      .build();
    this.connection.on("ReceiveMessage", function(user, message) {
      thisVue.messages.push({ user, message });
      console.log({ user, message });
    });
    this.connection.on("ReceiveCaller", function(message) {
      let user = "自己";//这里为了push不报错，我就弄了一个默认值。
      thisVue.messages.push({ user, message });
      console.log({ user, message });
    });
    this.connection.start();
  }
};
</script>

　　3. 运行效果如下

　　

　　4. 至此，vue客户端搭建完成