node.js - 使用 socket.io、node.js 和 mongodb 更新服务器端的 ejs 变量

Question

我正在使用 mongodb 和 mongoose 来维护跨客户的股票列表。当一个用户进行更改时，我想使用 socket.io 同时更新列表。我可以连接到套接字并更新客户端 JavaScript，但不能更改服务器端的变量。

app.js - 服务器

// connect to socket.io
io.on('connection', function (socket) {
   console.log('Client Connected..');

    ///retrieve new stock from client
    socket.on('submitStock', function (data) {
       console.log(data);
       ///do mongodb stuff here

       ///send new stocks to all clients
       socket.emit('activeStocks', data);
     });
});

script.js - 客户端

var socket = io.connect();

///connect to socket
socket.on('connect', function (data) {
   socket.emit('join', 'Hello World from client');
});

///use submit button to send the new stock to server
$('#addStock').on('submit', function(e){
    //var stockList = $('#stockList');
    socket.emit('submitStock', 'here is the data');
});

//retrieve the new stock from the server and update list
socket.on('activeStocks', function(data) {
   //how to update activeStocks here??
   console.log(data);
});

索引.ejs

<% if (message.length > 0) { %>
   <div class="alert alert-danger"><p><%= message %></p></div>
<% } %>

<div class="container">
  <form id="addStock" action="/add" method="post">
    <div class="form-inline">
      <input type="text" class="form-control" name="stockTicker" placeholder="Enter a stock ticker">
      <button type="submit" class="btn btn-primary"><span>Add Stock</span></button>
    </div>
  </form>
</div>

<% if (activeStocks) { %>
  <% for (var i=0; i< activeStocks.length; i++) { %>
    <div> <%- activeStocks[i] %></div>
  <% } %>
<% } %>

Answer 1

1. 假设我们在index.js中有一个div，让它为<div id="stocks"> ,
2. 让data是一个字符串数组，

尝试以下代码:

socket.on('activeStocks', function(data) {
    document.getElementById('stocks').innerHTML = '';
    data.forEach( function (stock) {
        document.getElementById('stocks').innerHTML += stock + '<br>';
    });
});