jQuery $（window）.load（）;没有<！DOCTYPE>的网页上的事件不会触发宣言？ （...在chrome扩展内容脚本中） [英] Does the jQuery $(window).load(); event not fire on pages without a <!DOCTYPE> declaration? (...in a chrome extension content script)
问题描述
我正在使用一个Google Chrome浏览器扩展程序来处理网页，但在部分加载（DOM）或完全加载（使用图像）之后。
I'm working on a Google Chrome extension that manipulates a webpage, but after it is either partially loaded (the DOM) or fully loaded (with images).
现在看来，很多网站使用
It seems that many sites nowadays use the
<!DOCTYPE html>
声明，或其中的一些变体，但其他许多则没有。问题主要是关于HTML doctypes ...我不知道其他的。
declaration, or some variation of it, but many others do not. The question is mainly about HTML doctypes...I'm not sure about the others.
假设如果一个网页没有DOCTYPE声明是安全的，那么$（window）.load（）;不会被解雇？
Is it safe to assume that if a webpage does not have the DOCTYPE declaration, then $(window).load(); will not be fired?
最初我使用$（document）.ready（）; （当DOM加载时），但后来切换到$（window）.load（）; （让图像加载）。
In the beginning I was using $(document).ready(); (for when the DOM is loaded), but later switched to $(window).load(); (to let the images load too).
事情是，现在$（window）.load（）;如果没有DOCTYPE，似乎不起作用。 $（文件）。就绪（）;似乎可以在所有页面上工作，无论是否声明DOCTYPE。
The thing is, now $(window).load(); does not seem to work if there is no DOCTYPE. $(document).ready(); seems to work on all pages, regardless of whether a DOCTYPE is declared or not.
也许这对于同样问题的其他人来说可能是有用的。我搜了一下，没有找到决定性的答案。看来我最终会使用这样的东西：
Maybe this can be useful for others with this same issue. I searched a bit and didn't find a decisive answer. It seems that I will end up using something like this:
if (window.document.doctype != null) {$(window).load(checkEntries);}
if (window.document.doctype == null) {$(document).ready(checkEntries);}
我猜我的问题是...是否需要检查DOCTYPE才能知道要使用哪个事件？或者我在这里缺少一些东西？
I guess my question is... Is this normal to have to check for the DOCTYPE to know which event to use? Or am I missing something here?
基本上，为什么$（window）.load（）;如果没有DOCTYPE声明，似乎不会触发？
Basically, why does $(window).load(); seem not to fire if there's no DOCTYPE declaration?
推荐答案
基本上，你不应该使用$（window）.load ），因为它不完全支持。如果你真的需要它，那么上面的解决方案是你能做的最好的。 jQuery页面很好地总结了这些注意事项：
Basically, you shouldn't be using $(window).load(), since it's not fully supported. If you really need it, then your solution above is the best you can do. The jQuery page sums up the caveats nicely:
使用图像时加载事件的注意事项
Caveats of the load event when used with images
开发人员尝试使用.load（）
快捷方式解决的常见问题是在图像（或
图像的集合）已完全加载时执行功能。有几个已知的警告，
这个应该注意。这些是：
A common challenge developers attempt to solve using the .load() shortcut is to execute a function when an image (or collection of images) have completely loaded. There are several known caveats with this that should be noted. These are:
- 它的工作不一致也不可靠地跨浏览器
- 如果图像src设置为与之前相同的src，则在WebKit中正常启动
- 它没有正确地起泡DOM树
- 可以对于已经在浏览器缓存中的图像，停止触发
- It doesn't work consistently nor reliably cross-browser
- It doesn't fire correctly in WebKit if the image src is set to the same src as before
- It doesn't correctly bubble up the DOM tree
- Can cease to fire for images that already live in the browser's cache
URL： http://api.jquery.com/load-event/
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