javascript - Javascript 对象中的属性范围

Question

我在控制台中收到此错误。我的 for 循环中发生错误不知道为什么，但是当我 console.log(manchesterUnited.[0].salary); 时我没有得到错误。我是 JS 新手，所以这可能是小事。 未捕获类型错误:无法读取未定义的属性“工资”。

var footballer = function(name, position, age, salary, number) {
  this.name = name;
  this.position = position;
  this.age = age;
  this.salary = salary;
  this.number = number;
}

var manchesterUnited = [];
manchesterUnited[0] = new footballer("Zlatan", "striker", 37, 20, 9);
manchesterUnited[1] = new footballer("Rooney", "forward", 33, 15, 10);

var totalSalary = 0;

for(var i = 0; i <= manchesterUnited.length; i++){
    totalSalary = manchesterUnited[i].salary + totalSalary;
}

console.log(totalSalary);

谢谢。

Answer 1

在 for 循环中，您有:

i <= manchesterUnited.length

应该是:

i < manchesterUnited.length