简体中文(ZH-CN) English(EN) 繁体中文(ZH-TW) 日本語(JA) 한국어(KO) Melayu(MS) Français(FR) Deutsch(DE)
Home > Web Front-end > JS Tutorial > body text

JS uses the ajax method to obtain the specified field value in the head information of the specified url_javascript skills

WBOY
Release： 2016-05-16 16:07:51
Original
2234 people have browsed it

The example in this article describes how JS uses the ajax method to obtain the specified field value in the head information of the specified URL. Share it with everyone for your reference. The specific analysis is as follows:

The following JS code is used to obtain the Last modified attribute in the head information of ajax_info.txt, and the last modification time

<!DOCTYPE html>
<html>
<head>
<script>
function loadXMLDoc(url)
{
var xmlhttp;
if (window.XMLHttpRequest)
 {// code for IE7+, Firefox, Chrome, Opera, Safari
 xmlhttp=new XMLHttpRequest();
 }
else
 {// code for IE6, IE5
 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
 }
xmlhttp.onreadystatechange=function()
 {
 if (xmlhttp.readyState==4 && xmlhttp.status==200)
  {
  document.getElementById('p1').innerHTML="Last modified: " + xmlhttp.getResponseHeader('Last-Modified');
  }
 }
xmlhttp.open("GET",url,true);
xmlhttp.send();
}
</script>
</head>
<body>
<p id="p1">The getResponseHeader() function is used to return specific header information from a resource, like length, server-type, content-type, last-modified, etc.</p>
<button onclick="loadXMLDoc('ajax_info.txt')">Get "Last-Modified" information</button>
</body>
</html>
Copy after login

I hope this article will be helpful to everyone’s JavaScript programming design.

Related labels：
ajax js url designation method Obtain
source：php.cn
Previous article：Custom jQuery plug-in method to implement forced object redrawing_jquery Next article：Detailed explanation of fiber (fiber) library in nodejs_node.js
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Articles by Author
Latest Issues
Can a workerpool declared in multiple routes still maintain its cpu usage without caring about the threshold I'm hoping to find a node.js system with a workerpool to handle CPU intensive tasks, but I...
From 2024-04-06 19:54:23
0
1
444
Scatterplot points do not maintain values ​​when zooming in d3.js This is my first time using d3.js, so please bear with me. I implemented it as pure JavaSc...
From 2024-04-06 18:16:26
0
1
403
Show hidden side panels: checked I would like to have a navigation menu in the side panel with the ability to switch to vie...
From 2024-04-06 15:49:33
0
1
319
Should we use SSG to deploy dashboards created with Nuxt.js? We will develop a dashboard for internal use using Nuxt.js. Since this will be an internal...
From 2024-04-06 13:17:44
0
1
493
Electron gets AppData on preload How to get the preloaded AppData directory? Background.js[...]asyncfunctioncreateWindow(){...
From 2024-04-06 11:05:31
0
1
417
Related Topics
More>
Popular Recommendations
Popular Tutorials
More>
Related Tutorials
Popular Recommendations
Latest courses
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template
About us Disclaimer Sitemap
php.cn：Public welfare online PHP training，Help PHP learners grow quickly！