Javascript闭包函数参数？ [英] Javascript closures function parameters?

问题描述

代码属于javascriptissexy.com
我的问题是为什么调用mjName（Jackson）返回这个名人是迈克尔·杰克逊？
是否为ANY外部函数中给出的第二个参数，说到js = inner函数参数？
有人可以非常详细地解释整个概念吗？

Code belongs to javascriptissexy.com My question is why invoking mjName ("Jackson") returns "This celebrity is Michael Jackson"? Is it that second parameter given in ANY outer function always, says to js = inner function parameter? Could someone explain the whole concept in great detail?

function celebrityName (firstName) {
    var nameIntro = "This celebrity is ";
// this inner function has access to the outer function's variables, including the parameter
    function lastName (theLastName) {
        return nameIntro + firstName + " " + theLastName;
    }
    return lastName;
}

var mjName = celebrityName ("Michael");
    // At this juncture, the celebrityName outer function has returned.

// The closure (lastName) is called here after the outer function has returned above
// Yet, the closure still has access to the outer function's variables and parameter
mjName ("Jackson"); // This celebrity is Michael Jackson

推荐答案

celebrityName（Michael）（Jackson）;

步骤：

1. celebrityName（Michael）返回函数lastName（theLastName）


2. （Jackson）传递给函数lastName


3. 函数lastName（theLastName）在执行时打印字符串

参数从左到右外部到内部调用的方法。

Arguments from left to right go from outer to inner called methods.

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