JavaScript 中匿名函数的 removeEventListener [英] removeEventListener on anonymous functions in JavaScript

问题描述

我有一个包含方法的对象.这些方法被放入匿名函数内的对象中.它看起来像这样:

I have an object that has methods in it. These methods are put into the object inside an anonymous function. It looks like this:

var t = {};
window.document.addEventListener("keydown", function(e) {
    t.scroll = function(x, y) {
        window.scrollBy(x, y);
    };
    t.scrollTo = function(x, y) {
        window.scrollTo(x, y);
    };
});  

(还有很多代码，但这足以说明问题)

(there is a lot more code, but this is enough to show the problem)

现在我想在某些情况下停止事件侦听器.因此，我正在尝试执行 removeEventListener，但我不知道如何执行此操作.我在其他问题中读到，无法对匿名函数调用 removeEventListener，但在这种情况下也是如此吗?

Now I want to stop the event listener in some cases. Therefore I am trying to do a removeEventListener but I can't figure out how to do this. I have read in other questions that it is not possible to call removeEventListener on anonymous functions, but is this also the case in this situation?

我在匿名函数内部创建了一个方法，因此我认为这是可能的.看起来像这样:

I have a method in t created inside the anonymous function and therefore I thought it was possible. Looks like this:

t.disable = function() {
    window.document.removeEventListener("keydown", this, false);
}

为什么我不能这样做?

有没有其他(好的)方法可以做到这一点?

Is there any other (good) way to do this?

奖金信息；这只需要在 Safari 中工作，因此缺少 IE 支持.

Bonus info; this only has to work in Safari, hence the missing IE support.

推荐答案

我相信这是匿名函数的重点，它缺少名称或引用它的方法.

I believe that is the point of an anonymous function, it lacks a name or a way to reference it.

如果我是你，我会创建一个命名函数，或者把它放在一个变量中，这样你就可以引用它.

If I were you I would just create a named function, or put it in a variable so you have a reference to it.

var t = {};
var handler = function(e) {
    t.scroll = function(x, y) {
        window.scrollBy(x, y);
    };
    t.scrollTo = function(x, y) {
        window.scrollTo(x, y);
    };
};
window.document.addEventListener("keydown", handler);

然后您可以删除它

window.document.removeEventListener("keydown", handler);   

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