javascript - 从基类访问和执行子类中的函数

Question

是否可以从基类访问子类成员并执行子函数？

例如:

class ChildClass extends BaseClass {

    protected childMember = 'someName';

    constructor() {
        super();
        super.runBaseFn();
    }

    runChildFn() {
        console.info('child fn');
    }
}

class BaseClass {

    runBaseFn() {
       if (child.childMember === 'someName') {
           child.runChildFn();
       }
    }
}

这可以完成runBaseFn中的代码吗？或者有类似的解决方案吗？

Answer 1

您需要在父类中声明:

class BaseClass {
    protected childMember: string;

    runBaseFn() {
       if (this.childMember === 'someName') {
           this.runChildFn();
       }
    }

    protected runChildFn() {}
}

class ChildClass extends BaseClass {
    constructor() {
        super();

        this.childMember = 'someName';
        super.runBaseFn();
    }

    runChildFn() {
        console.info('child fn');
    }
}

( code in playground )

您可以将父类设为抽象:

abstract class BaseClass {
    protected childMember: string;

    runBaseFn() {
       if (this.childMember === 'someName') {
           this.runChildFn();
       }
    }

    protected abstract runChildFn();
}