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As shown below:
//首先定义一个构造函数Hello function Hello(){ alert(1); } //定义一个函数表达式 var getName = function(){ alert(2); } //实例化对象,下面这两个如果构造函数没有形参的话,实例化的时候构造函数可以不加括号(推荐加上); var p = new Hello; var p1 = new Hello(); //但是用下边的方式调用getName函数的时候,构造函数有没有括号可就不一样了; new Hello.getName(); //这种执行顺序是先执行Hello.getName(),然后在使用new关键字; new Hello().getName;//这种是先new Hello()一个对象,然后对象调用getName方法;
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