如何扩展javascript类

Question

为什么Child类没有echo()方法？

Parent = function(){
    this.name = 'abc';
}

Parent.prototype.echo = function(){
    alert(this.name);
}

Child = function(){
    $.extend(this,  Parent);
}

var x = new Child();

x.echo();

我该怎么做才能继承Javascript中的父类？

Answer 1

您需要设置的原型Child来Parent.

function Parent() {
    this.name = 'abc';
}

Parent.prototype.echo = function () {
    alert(this.name);
}

function Child() {

}

Child.prototype = new Parent()

var x = new Child();

x.echo();