javascript - 数组中的对象位于构造函数中

Question

当我console.log时，这段代码:

 var Student = function(name, address, gpa){

    console.log(this);
    this.name = name;
    this.address = address;
    this.gpa = gpa;

    console.log("name is equal to " + name);
    console.log("address is equal to " + address);
    console.log("gpa is equal to " + gpa);
};



    var studentCall = [
    new Student ({
        name: "Marshae Hannor",
        address:{
            street: "345 Main St",
            city: "Smyrna",
            state: "GA"},
        gpa: [2.5, 3.5, 4.0]}),
    new Student ({
        name: "Vernon Owens",
        address:{
            street: "439 Serious St",
            city: "Baltimore",
            state: "MD"},
        gpa: [3.5, 3.2, 3.7]})
];

这是我在 console.log 中得到的内容

Object {}
main2.js (line 39)
name is equal to [object Object]
main2.js (line 44)
address is equal to undefined
main2.js (line 45)
gpa is equal to undefined
main2.js (line 46)
Object {}
main2.js (line 39)
name is equal to [object Object]
main2.js (line 44)
address is equal to undefined
main2.js (line 45)
gpa is equal to undefined

有人可以帮助我理解我做错了什么吗？谢谢

Answer 1

在对 Student 的调用中，您传入一个单个参数，它是一个如下所示的对象:

{
    name: "Marshae Hannor",
    address:{
        street: "345 Main St",
        city: "Smyrna",
        state: "GA"},
    gpa: [2.5, 3.5, 4.0]
}

但是您的 Student 函数期望接收三个离散参数。因此，您可以在不使用 { 和 } 的情况下调用它，并且不给出参数名称:

var studentCall = [
    new Student (
        "Marshae Hannor",
        {
            street: "345 Main St",
            city: "Smyrna",
            state: "GA"},
        [2.5, 3.5, 4.0]),
    new Student (
        "Vernon Owens",
        {
            street: "439 Serious St",
            city: "Baltimore",
            state: "MD"},
        [3.5, 3.2, 3.7])
];

或者，修改 Student 以期望仅接收具有这些属性的单个对象:

var Student = function(obj){

    console.log(this);
    this.name = obj.name;
    this.address = obj.address;
    this.gpa = obj.gpa;

    console.log("name is equal to " + this.name);
    console.log("address is equal to " + this.address);
    console.log("gpa is equal to " + this.gpa);
};