如何暂停javascript直到完成某件事? [英] How to pause javascript until something is done?

问题描述

为了尽快，我现在将跳至该主题. 我想在加载jQuery之前延迟脚本.

To be as fast as possible, I will jump into the topic right now. I want to delay the script before jQuery is loaded.

这是我的问题:我有一些代码，当尚未加载jQuery时会自动插入jQuery.js:

Here is my problem: I have code which inserts jQuery.js automatically when jQuery isn't loaded yet:

if(typeof jQuery=="undefined") {
    var s=document.createElement("script");
    s.type="text/javascript";
    s.async=true;
    s.src="http://code.jquery.com/jquery-1.5.1.min.js";
    var x=document.getElementsByTagName("script")[0];
    x.parentNode.insertBefore(s, x);
}

$(document).ready(function() {
    //My code goes here, right?
});

插入脚本的效果很好，但是问题是$(document).ready()不会等到脚本完全加载后，在加载脚本时会立即跳下.我想在那儿停顿，该怎么办?

It works perfectly to insert the script, but the problem is $(document).ready() does not wait until the script is loaded completely, it jumps down immediately while the script is being loaded. I want to pause right there, what should I do?

推荐答案

就像注释中提到的狼一样，这应该不成问题-$(document).ready()仅在加载jQuery时才起作用.

Like cwolves mentioned in the comment, this shouldn't be a problem - $(document).ready() should only work when jQuery is loaded.

但是，如果发现要做需要等到加载完成，就可以这样:

However, if you find that you do need to wait until it's loaded, you could so something like this:

if(typeof jQuery=="undefined")
{
    var s=document.createElement("script");
    s.type="text/javascript";
    s.async=true;
    s.src="http://code.jquery.com/jquery-1.5.1.min.js";
    var x=document.getElementsByTagName("script")[0];
    x.parentNode.insertBefore(s, x);
    wait();
}

//...

function wait() {
    if(typeof jQuery=="undefined")
    {
        setTimeout(wait, 200);
    }
    else {
        //jQuery is loaded, do what you need to
        $(document).ready(docLoaded);
    }
}

根据此帖子改编自使用Greasemonkey脚本加载jQuery

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