javascript - 错误 : Type '{}' is missing the following properties from type

Question

interface Person {
  name: string;
  surname: string;
}
let person1: Person = {};

person1.name = "name"
person1.surname = "surname"

当我声明 person1 时，我收到此错误:
Type '{}' is missing the following properties from type Person

Answer 1

这是一个更好的方法:

let person1: Person = {name: '', surname: ''};

但是，如果您想要完全为空的对象，则可以像这样破解它:

let person1: Person = {} as Person;

评论后更新:
看看这个 unpredictableFunction :

const unpredictableFunction = (): string|number|string[] => {
  return Math.random() > 0.5 ? 'string' : Math.random() > 0.5 ? 9999 : ['1', '2', '3']
};

它可能返回数字，也可能返回字符串，也可能返回字符串数组

const person: Person = {name: '', surname: ''};
person.name = unpredictableFunction (); // this is a case you are talking about

在这种情况下，您会看到 Type 'string | number | string[]' is not assignable to type 'string'.答案是:
查看您的代码并确保仅将字符串分配给 Person 属性，
或者更新接口(interface)以准备好不同的值:

interface Person {
  name: string | number | string[];
  surname: string; 
}