如何从构造函数内部返回构造函数的对象

Question

How can I return the object from constructor from inside the constructor?

  function consFunc() { this.flag = 'someFlag'; this.pol = 'somePole'; } consFunc.prototype.foo = function(){ console.log(this.flag); } var obj = new consFunc(); obj.foo(); 

This is how usually I make object from constructor. How can I return object from inside the constructor function so I no need to write var obj = new consFunc(); I just simply call obj.foo(); for my need, is it possible?

Answer 1

If you want to have an object with a simple function on it you can simply write

var consObj = {
  flag: 'someFlag',
  pol: 'somePole',       
  foo: function() { console.log( this.flag ); }
}

consObj.foo() // 'someFlag'

Answer 2

You could wrap your constructor in another function and return new consFunc(); from that function:

 function obj() { function consFunc() { this.flag = 'someFlag'; this.pol = 'somePole'; } consFunc.prototype.foo = function () { console.log(this.flag); } return new consFunc(); } // now use it obj().foo() 

Answer 3

If you need some sort of singleton:

var obj = (function (){

    var flag = 'someFlag';
    var pol = 'somePole';   

    function foo(){      
        console.log(flag);
    }

    return {
      foo: foo
    };
})();

obj.foo();