javascript - 方法错误 : Method name not defined

<分区>

为什么这段代码不起作用？我正在尝试使用该方法来添加属性，然后将添加的属性分配给它自己的值。

function howLongILivedSomewhere(college, home1, home2) {
    this.birthHome = 18;
    this.college = college;
    this.home1 = home1;
    this.home2 = home2;

    this.calcYearsAlive = function() {
    return birthHome + college + home1 +home2;
    };

    this.yearsAlive = calcYearsAlive();
}

var me = new howLongILivedSomewhere(4, 2, 3);

console.log(me);

最佳答案

您在方法/属性调用期间错过了 this 关键字。像下面这样尝试。

  function howLongILivedSomewhere(college, home1, home2) {
    this.birthHome = 18;
    this.college = college;
    this.home1 = home1;
    this.home2 = home2;

    this.calcYearsAlive = function() {
      return this.birthHome + this.college + this.home1 + this.home2;
    };

    this.yearsAlive = this.calcYearsAlive();
}

var me = new howLongILivedSomewhere(4, 2, 3);

console.log(me.yearsAlive); // output: 27