通过参数调用去抖函数 [英] Debounce function calls by their arguments

问题描述

David Walsh在此处实施了很好的辩论。

David Walsh has a great debounce implementation here.

// Returns a function, that, as long as it continues to be invoked, will not
// be triggered. The function will be called after it stops being called for
// N milliseconds. If `immediate` is passed, trigger the function on the
// leading edge, instead of the trailing.
function debounce(func, wait, immediate) {
    var timeout;
    return function() {
        var context = this, args = arguments;
        var later = function() {
            timeout = null;
            if (!immediate) func.apply(context, args);
        };
        var callNow = immediate && !timeout;
        clearTimeout(timeout);
        timeout = setTimeout(later, wait);
        if (callNow) func.apply(context, args);
    };
};

我在生产中使用它并且效果很好。

I am using it in production and it works great.

现在我遇到了一个更复杂的去抖动案例。

Now i have encountered a bit more complex case of debounce need.

我有一个事件用这样的参数调用一个事件处理程序：
$（elem）.on（'onSomeEvent'，（e）=> {handler（eX）}）;

I have an event that calls an event handler with a param like this: $(elem).on('onSomeEvent', (e) => {handler(e.X)} );

我很乐意经常触发这个事件并且每秒调用处理程序1000次。我不需要去除处理程序本身。
但在我的情况下，对于每个eX，我希望在一段时间内只调用一次，比如说250ms。

I am ok with this event being triggered frequently and calling the handler even 1000 times a second. I don't need to debounce the handler itself. But in my case, for each e.X, i want it to be called just once in a period, say 250ms.

我在想创建一个两个eX保持x和最后运行时间的维数组，但我不想声明任何全局变量。

I was thinking of creating a two dimensional array which holds the x and the last run time, but i don't want to declare any global variables.

任何想法？

*编辑*

阅读@Tim Vermaelen后，我已实施了像这样，它工作：

After reading @Tim Vermaelen answer i have implemented it like this, and it worked:

export function debounceWithId(func, wait, id, immediate?) {
        var timeouts = {};
        return function () {
            var context = this, args = arguments;
            var later = function () {
                timeouts[id] = null;
                if (!immediate) func.apply(context, args);
            };
            var callNow = immediate && !timeouts[id];
            clearTimeout(timeouts[id]);
            timeouts[id] = setTimeout(later, wait);
            if (callNow) func.apply(context, args);
        };
    };

推荐答案

我总是使用以下内容：

var debounce = (function () {
    var timers = {};

    return function (callback, delay, id) {
        delay = delay || 500;
        id = id || "duplicated event";

        if (timers[id]) {
            clearTimeout(timers[id]);
        }

        timers[id] = setTimeout(callback, delay);
    };
})(); // note the call here so the call for `func_to_param` is omitted

我不相信有与您的解决方案有很大不同，除了我可以在事件中添加唯一ID。如果我理解正确的话，你必须将它包裹在处理程序（eX）中。

I don't believe there's much difference with your solution except for the fact I can add unique id's in the events. You'll have to wrap this around handler(e.X) if I understand correctly.

debounce(func_to_param, 250, 'mousewheel');
debounce(func_to_param, 250, 'scrolling');

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