varutil=require('util');functionBase(){this.name='base';this.base=1991;this.sayHello=function(){console.log('Hello'+this.name);};}Base.prototype.showName=function(){console.log(this.name);};functionSub(){this.name='sub';}util.inherits(Sub,Base);varobjSub=newSub();console.log(objSub);很明顯會打印{name:'sub'}Sub僅僅繼承了Base在原型中定義的函數，而構造函數內部創造的base屬性和sayHello函數都沒有被Sub繼承。那么如何繼承構造函數內部創造的base屬性和sayHello函數求解答