Arrays 无法使用for循环获取数组值

我向数组中添加如下值：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

控制台显示的结果如下：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

我使用了这样的for循环：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

为什么for循环没有显示错误？我错过了什么

---

谢谢您的帮助。

您的第一个问题是AnArray变量不是数组，而是对象。您将按如下方式声明它：

ansArray = {question:id[count], answer: 'a'};

这将创建一个包含问题字段和答案字段的对象。您可以这样声明对象：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

您可以这样声明数组：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

所以，你可能想得到这样的东西：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

这将为您提供一个包含单个对象的数组。我猜你想要这样的东西：

ansArray = {question:id[count], answer: 'a'};

(
    {
        answer = a;
        question=1;
    },
    {
        answer =d;
        question=2;
    }
    //......

    //.......
)

for (i=0;i<20;i++){
    alert(ansArray[i].answer); //This comes with undefined error
    alert(ansArray[i].question); //undefined
}

someObject = {};

someArray = [];

ansArray = [{question:0, answer:'a'}];

var ansArray = [];
ansArray[0] = {question:0, answer:'a'};
ansArray[1] = {question:1, answer:'d'};
...
ansArray[19] = {question:19, answer:'b'};

您将能够使用原始循环代码对此进行循环。使用javascript标记也会很有帮助