使用JavaScript和jQuery简单的长轮询的例子 [英] Simple long polling example with JavaScript and jQuery

问题描述

我试图创建一个实时网站分析仪表盘创造一个开放的HTTP连接使用jQuery /异步的JavaScript来更新服务器轮询到数据服务器，当它们发生。

其明显的启动将是使用 XMLHtt prequest 对象或jQuery的 $。阿贾克斯方法来发送一个 GET 或 POST 请求到服务器异步请求的一些数据。

然而，除了使用的setInterval 方法一次发送一个请求每个我不知道怎么样以向服务器持久的连接。基本上，我只是想发的一个http请求并确保与服务器的连接保持开放投票！

我的例子$ C $与的setInterval c是如下：

 ＆LT; D​​IV ID =分析＆GT;＆LT; / DIV＆GT;
＆LT;脚本＆GT;
VAR分析=的document.getElementById（'分析'）;
的setInterval（函数（）{
    $阿贾克斯（网址：{url：http://server.com/，成功：功能（数据）{
        analytics.innerHTML =数据;
    }，数据类型：JSON}）;
}，30000）;
＆LT; / SCRIPT＆GT;
 

解决方案

在线搜索，这是我一直在寻找的答案后为其不使用 sockets.io 也不的WebSockets ，但不使用 的jQuery 通过采取优势其完整方法来创建一个人工循环：

 ＆LT; D​​IV ID =分析＆GT;＆LT; / DIV＆GT;
＆LT;脚本＆GT;
VAR分析=的document.getElementById（'分析'）;
（函数民调（）{
    $阿贾克斯（网址：{url：服务器，成功：功能（数据）{
        analytics.innerHTML =数据;
    }，数据类型：JSON，完整的：民调显示，超时：30000}）;
}）（）;
＆LT; / SCRIPT＆GT;
 

来源为Technoctave田戴维斯：<一href=\"http://techoctave.com/c7/posts/60-simple-long-polling-example-with-javascript-and-jquery\">http://techoctave.com/c7/posts/60-simple-long-polling-example-with-javascript-and-jquery

I'm trying to create a real-time website analytics dashboard which creates an open HTTP connection to the server using jQuery/JavaScript asynchronously to poll the server for updates to the data as and when they occur.

The obvious start for this would be to use an XMLHttpRequest object or jQuery's $.ajax method to send a GET or POST request to the server asynchronously requesting some data.

However, beyond sending one request at a time using a setInterval method every 30 seconds I am not sure how to make the connection to the server persistent. Basically, I only want to send one http request and ensure the connection to the server stays open for polling!

My example code with setInterval is as follows:

<div id="analytics"></div>
<script>
var analytics = document.getElementById('analytics');
setInterval(function(){
    $.ajax({ url: "http://server.com/", success: function(data){
        analytics.innerHTML = data;
    }, dataType: "json"});
}, 30000);
</script>

解决方案

After searching online, this was the answer I was looking for which doesn't use sockets.io nor WebSockets but does use jQuery by taking advantage of its complete method to create an artificial loop:

<div id="analytics"></div>
<script>
var analytics = document.getElementById('analytics');
(function poll(){
    $.ajax({ url: "server", success: function(data){
        analytics.innerHTML = data;
    }, dataType: "json", complete: poll, timeout: 30000 });
})();
</script>

Source is Tian Davis from Technoctave: http://techoctave.com/c7/posts/60-simple-long-polling-example-with-javascript-and-jquery

这篇关于使用JavaScript和jQuery简单的长轮询的例子的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！