javascript中的函数只能调用一次 [英] Function in javascript that can be called only once

问题描述

我需要创建一个只能执行一次的函数，在第一次执行后不会被执行。我从C ++和Java中知道可以做这些工作的静态变量，但是我想知道是否有更优雅的方法来实现？

I need to create a function which can be executed only once, in each time after the first it won't be executed. I know from C++ and Java about static variables that can do the work but I would like to know if there is a more elegant way to do this?

推荐答案

如果通过不执行，您的意思是多次调用时不会做任何事情，您可以创建一个关闭：

If by "won't be executed" you mean "will do nothing when called more than once", you can create a closure:

var something = (function() {
    var executed = false;
    return function () {
        if (!executed) {
            executed = true;
            // do something
        }
    };
})();

在回答@Vladloffe（现已删除）的评论时：使用全局变量，其他代码可能重置执行标志的值（您为其选择的任何名称）。关闭，其他代码无法做到这一点，无意中或故意。

In answer to the comment by @Vladloffe (now deleted): With a global variable, other code could reset the value of the "executed" flag (whatever name you pick for it). With a closure, other code has no way to do that, either accidentally or deliberately.

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