准备好 DOM 的 Javascript 模块模式

Question

我正在编写一个 JS 模块模式来测试代码并帮助我使用 JS Fiddle 理解该模式。我不明白的是，为什么第 25 行和第 26 行的“私有(private)方法”在通过 DOM 就绪引用时，其值为未定义。

JSFiddle

代码示例:

var obj = {
    key: "value"
};

var Module = (function () {

  var innerVar = "5";

  console.log("obj var in Module:");
  console.log(obj);

function privateFunction() {
    console.log("privateFunction() called.");
    innerFunction();

    function innerFunction() {
        console.log("inner function of (private function) called.");
    }
}

function _numTwo() {
    console.log("_numTwo() function called.");
}
return {
    test: privateFunction,
    numTwo: _numTwo

}


}(obj));


$(document).ready(function () {
    console.log("$ Dom Ready");
    console.log("Module in Dom Ready: ");
    console.log(Module.test());
});

Answer 1

您正在将调用 privateFunction 的返回结果输出到控制台，在本例中没有返回结果。

...
function privateFunction() {
    console.log("privateFunction() called.");
    innerFunction();

    function innerFunction() {
        console.log("inner function of (private function) called.");
    }
    return 'not undefined :)';
}
...

控制台输出:

obj var in Module: (index):30
Object {key: "value"} (index):31
$ Dom Ready (index):57
Module in Dom Ready:  (index):58
privateFunction() called. (index):34
inner function of (private function) called. (index):38
not undefined :) 

See the updated jsFiddle for details