在變量實例上訪問原型方法

Question

var Foo = (function() { 

    var cls = function() { 
     this.prototype = { 
      sayhi: function() { 
       alert('hi'); 
      } 
     }; 
    }; 

    cls.staticMethod = function() {}; 

    return cls; 

})(); 

var f = new Foo(); 

爲什麼我不能訪問我的sayhi方法？ this是否參考cls變量？

Answer 1

您試圖設置prototype屬性實例的cls。你真正想要做的是設置的cls本身prototype屬性：

var Foo = (function() { 

    var cls = function() {}; // Constructor function 

    cls.prototype = { // Prototype of constructor is inherited by instances 
     sayhi: function() { 
      alert('hi'); 
     } 
    }; 

    return cls; 

})();