Javascript（jquery） - 附加到一个事件的多个处理程序：如何只分离一个事件？ [英] Javascript (jquery) - Multiple Handlers attached to one event: How to detach only one?

问题描述

在这个模块中我正在研究我在窗口中有一个'resize'事件的监听器。每次运行模块时，我都需要检查是否已经有一个监听器注册到该事件并将其分离，以避免不必要的行为，内存泄漏等。

In this module I'm working on I have a listener to a 'resize' event in the window. Every time the module is ran, I need to check if there's already a listener registered to that event and detach it, in order to avoid unwanted behavior, memory leaks and etc.

到目前为止一切顺利，但是，在我们正在开发的这个应用程序中，有些处理程序已经附加到'resize'事件，我无法调用 $（window）.off（' resize'），因为这会刷新之前由其他插件或模块注册的所有其他事件处理程序。

So far so good, but, in this application we are working on, chances are that some handlers are already attached to the 'resize' event and I can't call $(window).off('resize'), as this would flush all the other event handlers previously registered by other plugins or modules.

正如那样说，我想知道是否有办法识别我的处理程序，只分离我自己注册的东西。如何在我的事件处理程序中设置标识符，以便在 .off（）函数中引用？

Being that said, I would like to know if there's a way to identify my handler and only detach things that I have registered myself. How do I set an identifier to my event handler in order to be referenced in the .off() function?

任何帮助都会很好。

推荐答案

这里有两个不同的建议。您可以为事件指定命名空间，也可以在绑定时传递无匿名函数。

Here 2 different suggestions. You can either give a namespace to your event or pass a none anonymous function when binding.

$(window).on('resize.event1', function(){});
$(window).on('resize.event2', function(){});

//Only turn off event 2
$(window).off('resize.event2');

jQuery允许您识别您的活动。此行为称为命名空间。当前事件和事件名称必须用点分隔。在这种情况下，我绑定2调整大小事件（点的左侧），一个名称 event1 ，另一个与 event2 。

jQuery allow you to identify your event. This behaviour is called namespace. The current event and the event name must be separate by a dot. In that case, i am binding 2 resize event (left side of the dot), one with the name event1 and the other with event2.

通过识别事件，您可以在对象具有多个相同事件时删除（或触发）单个事件。

By identifying the event, you can remove (or trigger) single event when an object have multiple of the same event.

$(window).trigger('resize'); //Trigger both;
$(window).trigger('resize.event2'); //Trigger event2;

使用命名函数的示例：

Example using named functions :

$(window).on('resize', function1);
$(window).on('resize', function2);

//Only turn off event 2
$(window).off('resize', function2);

如果传递的函数与当前事件函数匹配，则关联无匿名函数可以删除事件。因为 function2 === function2 ，只有第二个函数将被删除，因为 function1！== function2 ！

Associating a none anonymous function allow you to remove the event if the passed function match the current event function. Because function2 === function2, only the second function will be remove since function1 !== function2!

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