interface User { name: string location: string job: string } let user: User = { name: 'ArrayZoneYour', location: 'Beijing', job: 'FE', update: (info: User) => { user = { ...user, ...info } } } const getUserInfo: (key: 'name' | 'location' | 'job'): string...
interface Person { name: string; age: number; } let alan: Person = { name: "alan", age: 18, }; 1. 2. 3. 4. 5. 6. 7. 8. 9. 2.只读属性 interface Person { readonly name: string; age: number; } 1. 2. 3. 4. 只读属性用于限制只能在对象刚刚创建的时候修改其值。 此外Type...
interface StringArray { [index: number]: string; } let myArray: StringArray; myArray= ["Bob", "Fred"]; let myStr: string= myArray[0]; 上面例子里,我们定义了StringArray接口,它具有索引签名。 这个索引签名表示了当用number去索引StringArray时会得到string类型的返回值。 TypeScript支持两种索引签名...
fly():void} interface Person { age: number, talk():void; } type BirdMan= Bird &Person; let bm: BirdMan= {name: 'lee', fly() {}, age: 1, talk(){}} 2. 获取对象类型-typeof let user = {name: 'lee', age: 1, talk() {}}; type User=typeofuser;//相当于 {name: string,...
在这个例子中,interface和type都可以定义一个对象类型,并且在使用上几乎没有区别。 2. 扩展(Extend) 2.1interface的扩展 interface可以通过继承的方式进行扩展: interface User { name: string; age: number; } interface Admin extends User { role: string; ...
interfaceUser{name:string;age:number;}interfaceSetUser{(name:string,value:number):void;}typeUser={name:string;age:number;}typeSetUser=(name:string,value:number):void; 都允许拓展(extends) interface 和 type 都可以拓展,并且两者并不是相互独立的,也就是说 interface 可以 extends type, type 也可以 ...
interface User1 { [key: 'id']: string; // 错误 keyType不允许是字面量类型 } interface User2 { [key: 'id' | 'age']: string; // 错误 keyType不允许是字面量类型 } // 解决以上问题可以如果Record这个工具类型 type User3 = Record<'id', string>; // 正确 ...
一、type和interface使用方法? 1、interface基本用法 interfaceobj{obj1:string,obj2:string,fn1:()=>string}constuser:obj={obj1:"obj1",obj2:"obj2",fn1:():string=>{return"fn1"}}console.log(user.obj1)console.log(user.obj2)console.log(user.fn1()) ...
type MakePropertiesOptional<T> = { [K in keyof T]?: T[K] };interface User {id: number;name: string;age: number;}type OptionalUser = MakePropertiesOptional<User>;const user: OptionalUser = {id: 1,name: "John",age: 25,};
interface IPerson { readonly name: string; isMale: boolean; age?: number; } class Person implements IPerson { readonly name: string = ""; isMale: boolean = false; age?: number; } function createPerson(): IPerson { return { name: "", isMale: false, }; } 打个广告,我的新课:TypeS...