继承问题 ：求指教

Question

functionSuperType(){
this.name='s;'
this.colors=["red","blue","green"];
}
functionSubType(){
}
//inheritfromSuperType
SubType.prototype=newSuperType();
varinstance1=newSubType();
varinstance2=newSubType();
instance1.name='ssss';
instance1.colors=["red","blue"];
alert(instance1.colors);//"red,blue,green,black"
alert(instance1.name);//"ssss"
alert(instance2.colors);//"red,blue,green,black"
alert(instance2.name);//"s"
instance2.name为什么没有改变
functionSuperType(){
this.name='sdsd';
this.colors=["red","blue","green"];
}
functionSubType(){
//inheritfromSuperType
SuperType.call(this);
}
varinstance1=newSubType();
instance1.colors.name='aaaaaaa';
instance1.colors.push("black");
alert(instance1.colors);//"red,blue,green,black"
alert(instance1.name);//"a"
varinstance2=newSubType();
instance2.colors.name='bbbbbbb';
alert(instance2.colors);//"red,blue,green"
alert(instance2.name);//"a"
instance2.name和instance1.name都没有改变

Answer 1

读（console.log(a.key)）和写(a.key=1)的时候是不一样的，读的时候会一直查下去，写的时候发现本身没有就直接创建赋值了。newSubType（）时this指向当前新创建的instance，所以产出为{name,colors}。那你改对colors添加name是不会影响到name属性的。