Javascript语法：立即调用带参数的函数表达式（IIFE） [英] Javascript Syntax: Immediately Invoked Function Expression (IIFE) with parameters

问题描述

我一直看到这样的代码：

I have always seen code like this:

(function(){
   //code here
})();

此代码如何运作？哪个函数接收哪些参数？

How does this code work? Which function receives which parameters?

(function(factory){
   //code here
}(function($){
  //other code here
}));

推荐答案

function($){
  //other code here
}

此块已通过作为外部IIFE的参数。写这样可能更清楚：

This block is passed as a parameter to the outer IIFE. It might be clearer to write it like this:

var factoryDef = function($) { ... };

(function(factory) {
    // this is the outer IIFE
    var someVar = {};
    // you can call:
    factory(someVar);
    // the previous line calls factoryDef with param someVar
}(factoryDef));

所以 factory（someVar）是一样的as factoryDe​​f（{}）;后者只是 factory （函数 factoryDe​​f ）的值，其值为 someVar （ {} 。）

So factory(someVar) is the same as factoryDef({}); the latter is simply the value of factory (which is the function factoryDef) called with the value of someVar (which is {}.)

这有意义吗？

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