


JavaScript implementation method to determine whether a URL link is valid_javascript skills
Introduction
There is an address book system deployed on several servers at the same time, but there is a link to the address book on the homepage, linked to this system. The problem is that sometimes the server pointed to by the link fails, so I hope that on this server In case of failure (service unavailable), links to other servers can be pointed to.
Solution 1: XMLHTTP solution
The following code is excerpted from meizz's reply in [2]:
Disadvantages: Use ActiveXObject, so it is IE Only. Non-IE core browsers are not available.
Solution 2: jQuery extension
For the following content, please refer to [1]
Home page: http:/ /plugins.jquery.com/project/linkchecker
Demo page: http://sidashin.ru/linkchecker/
The downloaded compressed package contains calling examples.
Supplement:
If you target a The specific URL, just using jQuery without a plug-in, can be like this:
$.ajax({
url: 'http://some.url.com',
type: 'GET',
complete: function(response) {
if(response. status == 200) {
alert('valid');
} else {
alert('invalid');
}
}
});
Reference documents:
[1]http://zhidao.baidu.com/question/138740329.html?push=ql
[2]http://topic.csdn. net/t/20041214/16/3644539.html

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