Question

我试图遍历数组，只返回地址和包数，然后将数组中的包总数加起来。问题是，当我在codepen.io中全部编写这些代码时，它告诉我每个name属性都有一个意外的标识符错误。我知道我必须自己处理循环，但是这有什么问题呢？这是我在Codepen.io中看到的内容，如果想要查看Codepen显示的内容，则这里是链接：https://codepen.io/epbutterfield/pen/NBxMQb?editors=0012

我知道它非常简单，但是我必须有一个额外的标识符，或者会丢失一个标识符。...

var deliveryItinerary = [
  {  
    name: Doctor Allen Grant,
    address: '123 Jurassic Park Trail, Kualoa Ranch, Hawaii',
    zipcode: 96744,
    packages: 5
  },
  {
    name: Harry Potter,
    address: '4 Privet Drive, Manchester, England',
    zipcode: 81726,
    packages: 8
  },
  {
    name: Bowen Knight,
    address: '1600 Camelot Court, Liverpool, England',
    zipcode: 15064,
    packages: 2
  },
  {
    name: Van Helsing,
    address: '1462 Dracula\'s Castle, Valerious, Transylvania',
    zipcode: 18870,
    packages: 1
  }
];

for (i = 0; i < deliveries.length; i++){
  console.log(deliveryItinerary[i].address)
  console.log(deliveryItinerary[i].packages){
    deliveryItinerary.reduce[i].packages
  }
};

Answer 1

在您的name值周围添加引号，因为它们是字符串文字而不是JS变量。还可以使用一个额外的变量，称为totalPackages，以总结循环中的所有程序包。

var deliveryItinerary = [
  {  
    name: 'Doctor Allen Grant',
    address: '123 Jurassic Park Trail, Kualoa Ranch, Hawaii',
    zipcode: 96744,
    packages: 5
  },
  {
    name: 'Harry Potter',
    address: '4 Privet Drive, Manchester, England',
    zipcode: 81726,
    packages: 8
  },
  {
    name: 'Bowen Knight',
    address: '1600 Camelot Court, Liverpool, England',
    zipcode: 15064,
    packages: 2
  },
  {
    name: 'Van Helsing',
    address: '1462 Dracula\'s Castle, Valerious, Transylvania',
    zipcode: 18870,
    packages: 1
  }
];

var totalPackages = 0;
for (i = 0; i < deliveryItinerary.length; i++){
  console.log(deliveryItinerary[i].address);
  console.log(deliveryItinerary[i].packages);
  totalPackages += deliveryItinerary[i].packages;
};
console.log(totalPackages);

JavaScript：遍历对象数组并过滤特定的属性/属性

1 个答案: