有没有办法让实际的被调用函数用于实例化对象?
function A(){}
A.prototype.test = function(){};
function B(){}
B.prototype = Object.create(A.prototype);
B.prototype.test = function(){};
var x = new B();
alert(x.constructor); // alerts "A"
我也对跨浏览器支持感兴趣
感谢
答案 0 :(得分:1)
在这种继承之后,你需要显式设置'subclass'的构造函数。
...
B.prototype = Object.create(A.prototype);
B.prototype.constructor = B;
...
据我所知,没有办法自动执行此操作。即使谷歌的Closure库也有这样的东西;
var inherit = function(subClass, superClass) {
var temp = function() {};
temp.prototype = superClass.prototype;
subClass._super = superClass.prototype;
subClass.prototype = new temp();
subClass.prototype.constructor = subClass;
};
所以,如果你有一个带参数的构造函数,你可以简单地做一些像
这样的事情var ParentClass = function(arg1, arg2) {
this.arg1 = arg1;
this.arg2 = arg2;
};
ParentClass.prototype.show = function() {
console.log('Parent!');
console.log('arg1: ' + this.arg1);
console.log('arg2: ' + this.arg2);
};
var ChildClass = function(arg1, arg2, arg3) {
ParentClass.call(this, arg1, arg2);
this.arg3 = arg3;
};
inherit(ChildClass, ParentClass);
ChildClass.prototype.show = function() {
console.log('Child!');
console.log('arg1: ' + this.arg1);
console.log('arg2: ' + this.arg2);
console.log('arg3: ' + this.arg3);
};
<强> Example 强>