在Javascript中从对象中检索数组对象

Question

12345

我想访问phoneNumbers字段 所以我用

var obj={"firstName":"John","lastName":"Smith","isAlive":true,"age":25,"address":{"streetAddress":"21 2nd Street","city":"New York","state":"NY","postalCode":"10021-3100"},"phoneNumbers":[{"type":"home","number":"212 555-1234"},{"type":"office","number":"646 555-4567"},{"type":"mobile","number":"123 456-7890"}],"children":[],"spouse":null};

我得到一个数组，但没有＆＃34; phoneNumbers＆＃34; field.I想得到这样的东西：

phone=obj.phoneNumbers;

Answer 1

您可以添加该部分：

var phone = {"phoneNumbers" : obj.phoneNumbers};

虽然应该有充分的理由这样做（例如，需要将其传递给期望完全“x”的API）。单个属性对象与其单个属性的值一样有用。

Answer 2

你必须创建一个新对象

var phone = { "phoneNumbers": obj.phoneNumbers };

Answer 3

如何制作一个功能并将其用于其他类似用途：

function transform (prop, payload) {
  return { [prop]: payload };
}

并使用它：

phone = transform('phoneNumbers', obj.phoneNumbers);