确保jQuery事件处理程序执行顺序 [英] Ensure jQuery event handler execution order

问题描述

我认为事件处理程序按照注册的顺序进行处理。 （这是否正确？）如果是这样，那么如果我在脚本的开头附加一个事件处理程序，我可以绝对确定它会在后续处理程序附加到同一个事件之前触发？事件命名空间对此也有影响吗？事件处理程序是否串行触发（一个在下一个完成）或并行发生？

I think that event handlers are processed in the order that they are registered. (Is that correct?) If that is the case then if I attach an event handler at the beginning of my script, can I be absolutely certain that it will fire before subsequent handlers attached to the same event? Also do event namespaces have any effect on this? Are event handlers fired in series (one finishes before the next) or in parallel?

我想这样做，因为我的脚本依赖于视口大小，调整大小的事件，我需要不断的寻找。而不是在每个处理函数中重复调用 $（window）.width（），我想把一个处理程序放在脚本的顶部，保存code> $（window）.width（）到每个resize上的一个对象属性。然后在随后的处理程序中，我可以访问该属性，并确定它是最近的测量。

I want to do this because my script relies on the viewport size, which changes on the resize event, and I need to constantly look for it. Rather than calling $(window).width() repeatedly in each of my handler functions, I'd like to put a handler at the top of my script that saves $(window).width() to an object property on each resize. Then in subsequent handlers I can access the property and be certain that it is the most recent measurement.

我知道我可以创建一个自定义事件，一旦计算就触发已完成，并将后续处理程序附加到自定义事件。但是，我不想这样做，因为我需要保持与我们之后可能附加到resize事件的插件的互操作性。

I know I could create a custom event that triggers as soon as the calculation is done and attach subsequent handlers to the custom event. But, I'd don't want to do that because I need to maintain interoperability with plugins that come after mine that may also be attaching to the resize event.

推荐答案

如果您在任何其他脚本运行之前附加事件处理程序（即使只是一个插件），那么您的回调将始终处于起始状态。

If you attach your event handler before any other script has run (even just a plugin), then your callback will always fire first.

您可以通过数据对象检查事件处理程序的数组：

You can inspect the array of event handlers through the data object:

$(window).data('events');

注意：这是一种非记录的方法，可能无法正常工作。仅用于检查。

Note: this is a non-documented approach and might not work eventually. Use it for inspection only.

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