javascript - Typescript 实现接口(interface)属性

Question

我已声明接口(interface)如下

interface Base {
    required: string;
}

我已经在类中实现了接口(interface)，例如

class MyClass implements Base{
    method(): void {
        console.log(this.required);
    }
}

但是我收到以下错误

severity: 'Error' message: 'Class 'MyClass' incorrectly implements interface 'Base'. Property 'required' is missing in type 'MyClass'.' at: '5,7' source: 'ts'

severity: 'Error' message: 'Property 'required' does not exist on type 'MyClass'.' at: '7,26' source: 'ts'

如果我在类里面再次声明 required: string; 则不会出现错误

interface Base {
    required: string;
}

class MyClass implements Base{
 required: string;

    method(): void {
      this.required="ddd";
        console.log(this.required);
        // you can access HTMLElement
    }
}

var ss=new MyClass();
ss.method();

Answer 1

如果您不想删除 requried: string 两次，请使用 class instate interface 作为 Base 并扩展状态实现。

class Base {
    required: string;
}

class MyClass extends Base{
    method(): void {
      this.required="ddd";
        console.log(this.required);
        // you can access HTMLElement
    }
}

查看playground .