函数在接口和类中重载 - 如何？ [英] Functions Overloading in interface and classes - how to?

问题描述

我有这个界面：

interface IPoint {
    getDist(): string;
    getDist(x: number): any;
}

我需要一个班来实现它但是我无法做到在类中实现getDist（）方法
的语法..

and I need a class to implement it but I can't get the right syntax to implement the getDist() method in the class..

class Point implements IPoint {
    // Constructor
    constructor (public x: number, public y: number) { }

    pointMethod() { }

    getDist() {
        Math.sqrt(this.x * this.x + this.y * this.y);
    }
    // Static member
    static origin = new Point(0, 0);
}

它说：

类'Point'声明接口'IPoint'但不实现它：
类型'Point'和'IPoint'的属性'getDist'的类型是
不兼容：调用类型'（）=> void'和'{（）：string的签名;
（x：数字）：任意; }'不兼容

Class 'Point' declares interface 'IPoint' but does not implement it: Types of property 'getDist' of types 'Point' and 'IPoint' are incompatible:Call signatures of types '() => void' and '{ (): string; (x: number): any; }' are incompatible

这样做的正确方法是什么？

What's the proper way to do this?

谢谢

推荐答案

当您在类中声明该函数时，需要使用重载来装饰它：

When you declare the function in the class you need to decorate it with the overloads:

getDist(): string;
getDist(x: number): any;
getDist(x?: number): any {
    // your code
 }

这篇关于函数在接口和类中重载 - 如何？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！