TypeScript - 接口

1. 在面向对象的编程中, 接口是一种规范定义, 起到了一种限制和规范的作用


2. 自定义方法传入参数, 对json进行约束

    function run(json: {aaa: string, bbb: number}) {
        // ...
    }
    run({aaa: 'aaa', bbb: 123});


3. 属性接口 (interface), 对传入参数进行约束

    interface User {
        username: string;
        
        // 属性名加?号, 接口的可选属性, 这个参数可传可不传
        password?: string; 
    }

    function userInfo(user: User) {
        // user.username
        // user.password
    }
    
    userInfo({username: 'aaa', password: '123'});
    userInfo({username: 'aaa'});


4. 函数类型接口
    
    interface Fun {
        (aaa: string, bbb: number): string;
    }

    var fn: Fun = function(aaa: string, bbb: number): string {
        return 'ok';
    }


5. 类类型接口

    interface Animal {
        name: string;
        eat(food: string): void;
    }

    class Dog implements Animal {
        
        name: string;

        constructor(name: string) {
            this.name = name;
        }

        eat(food: string): void {
            // ...
        }
    }


6. 接口扩展 (接口可以继承接口)

    interface Animal {
        eat(food: string): void;
    }

    interface Person extends Animal {
        work(): void;
    }

    class teacher implements Person {
        
        eat(food: string): void {
            // ...
        }

        work(): void {
            // ...
        }
    }