getUserInfo(); // 错误信息:An argument for 'user' was not provided. getUserInfo({name: "coderwhy"}); // 错误信息:Property 'age' is missing in type '{ name: string; }' getUserInfo({name: "coderwhy", height: 1.88}); // 错误信息:类型不匹配 1. 2. 3. 4. 这样确实可以防止出现错误...
简单说一个点当我们只是需要在约束一个对象的结构时,使用interface在编译为js后,不会产生额外的信息,interface在编译为js后会被擦除;而如果使用class(包括abstract class),则会产生一个额外的对象,而实际上我们只是需要类型检查,这个对象就是无用的 关于TypeScript Team对于interface的定位,也许可以参考这篇blog:Walkt...
interface Point { y: number; }//等价于interface Point { x: number; y: number; } ⏰type 6. only interface can 🔊:在实际开发中,有的时候也会遇到interface能够表达,但是type做不到的情况:「给函数挂载属性」 interface FuncWithAttachment { (param: string):boolean; someProperty: number; } cons...
minute: number): ClockInterface; } interface ClockInterface { // ClockInterface 实例的描述 tick(); } // createClock 作用:实现对 constructor 的检查 function createClock(ctor: ClockConstructor, hour: number, minute: number): ClockInterface { return new ctor(hour, minute); // ctor 为传入的类,...
interface.js 文件代码如下: interfaceShape{name:string;width:number;height:number;color?:string;}functionarea(shape:Shape){vararea=shape.width*shape.height;return"I'm "+shape.name+" with area "+area+" cm squared";}console.log(area({name:"rectangle",width:30,height:15}));console.log(area...
function greet(person: Person): void { console.log("Hello, " + person.name);} let user: Person = { name: "Alice", age: 25 };greet(user);``` 2.1 可选属性和只读属性 接口中的可选属性在对象中可以不存在,用 `?` 表示;只读属性使用 `readonly` 关键字修饰。 ```typescriptinterface Book...
class Animal3{ constructor(public name:string){} } interface WithClassName{ new (name:string):Animal3 } function createClass(clazz:WithClassName,name:string){ return new clazz(name) } let a3 = createClass(Animal3,"别抖腿"); console.log(a3) class和interface的区别 class 类声明并实现方法 in...
type Foo = number | { someProperty: number } 当你需要继承或实现时,使用 interface 代码语言:javascript 代码运行次数:0 运行 AI代码解释 interface Foo { foo: string; } interface FooBar extends Foo { bar: string; } class X implements FooBar { foo: string; bar: string; } 风格指南 使用箭头函...
5、多余的属性检查 Excess Property Checks 如果多传了属性,会报错 6、函数类型 Function Types 7、类类型 Class Types 8、可继承 Extending Interfaces Like classes, interfaces can extend each other. This allows you to copy the members of one interface into another, which gives you more flexibility in...
interface SquareConfig { color?: string; width?: number; } function createSquare(config: SquareConfig): { color: string; area: number } { let newSquare = {color: "white", area: 100}; if (config.color) { // Error: Property 'collor' does not exist on type 'SquareConfig' newSquare....