javascript - JS变量范围: pushing into an array in one function and accessing it another function

Question

http://jsfiddle.net/ujapned5/

我正在尝试创建一个“初始化程序”函数，用于定义 CSS id 和类名。

function init() {

    //our empty array for pushing
    var DivNamingPushArray = [];

    //object where we define our properties that will be used later
    var namingScheme = {
        "parentId": {
            "firstChild": "blah",
            "secondChild": "blahblah",
            "thirdChild": "blahblahblah"
        }
    }

    //loop through the namingScheme object and push into array
    for (propOne in namingScheme) {
        DivNamingPushArray.push(propOne);
        for (propTwo in namingScheme[propOne]) {
            DivNamingPushArray.push(namingScheme[propOne][propTwo])
        }
    }
}

function execute() {

    //call the "init" function
    init();

    //this cannot be called
    console.log(DivNamingPushArray);

    //however, why can this be successfully called?
    console.log(propOne);
}

execute();

我真的更喜欢将这些函数分开，而不是将 execute 包含在 init 中。稍后还有其他函数需要调用 DivNamingPushArray 变量。

我正在查看有关变量作用域的 MDN 文档，但没有找到简单的解决方案...

Answer 1

我建议你使用第三个函数来分离你的逻辑

关于propOne，你可以在你的问题中看到我的评论，只需将var放在它的前面即可。

<强> Working example here

execute();

function init(app) {
    app.DivNamingPushArray = getNamingArray();
}

function execute() {
    var app = {};

    //call the "init" function
    init(app);

    console.log(app.DivNamingPushArray);

}

function getNamingArray() {
    //our empty array for pushing
    var DivNamingPushArray = [];

    //object where we define our properties that will be used later
    var namingScheme = {
        "parentId": {
            "firstChild": "blah",
            "secondChild": "blahblah",
            "thirdChild": "blahblahblah"
        }
    }

    //loop through the namingScheme object and push into array
    for (var propOne in namingScheme) {
        DivNamingPushArray.push(propOne);
        for (var  propTwo in namingScheme[propOne]) {
            DivNamingPushArray.push(namingScheme[propOne][propTwo])
        }
    }

    return DivNamingPushArray;
}