js继承的实现代码_javascript技巧-js教程-

Object.prototype.extendf= function (a,b){
if(!a||!b) return;
var fa = typeof a=="function";
var fb = typeof b=="function";
var cha = function(a,b){
for(var c in b){
if(a[c]==undefined)//子类重写
a[c]=b[c];
}
return a;//返回继承后的对象
}
if(fa&&fb){
b.apply(this,a.arguments);
cha(a,b);
this["base"] =new b;//通过base访问父类
return cha(this,b.prototype);
}
else if(!fa&&fb){
cha(a,new b);
a["base"]= new b;
return cha(a,b);
}else if(fa&&!fb){
cha(a,b);
this["base"]=b;
return cha(this,b);
}else if(!fa&&!fb){
a["base"]=b;
return cha(a,b);
}
}

js测试：