如何在JavaScript对象中调用函数？

Question

I'm trying to call the bar function inside foo but I can't seem to figure out how to do it. What am I missing or what am I not understanding?

 var foo = function() { function bar() { alert('bar'); } }; $.fn.mainfoo = function() { alert('mainfoo'); return this.each(function(key, value) { if ($(this).data('mainfoo')) return $(this).data('mainfoo'); var mainfoo = new foo(); $(this).data('mainfoo', mainfoo); }); }; var myfoo = $('body').mainfoo(); try { myfoo.data('mainfoo').bar(); } catch (e) { alert(e); } 

Answer 1

Change bar so that it is a property of foo :

 var foo = function(){ this.bar = function() { alert('bar'); } }; $.fn.mainfoo = function() { alert('mainfoo'); return this.each(function(key, value){ if ($(this).data('mainfoo')) return $(this).data('mainfoo'); var mainfoo = new foo(); $(this).data('mainfoo', mainfoo); }); }; var myfoo = $('body').mainfoo(); myfoo.data('mainfoo').bar(); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> 

Answer 2

you have a little oversight, inside on how to access to the bar method inside foo. So you need to return any from foo, will be an object and inside bar method. Here a demo , with a very little touched from yours:

var foo = function(){
    return {
    bar: function() {
    alert('bar');
    }
  }
};

$.fn.mainfoo = function() {
      console.log('mainfoo');

        return this.each(function(key, value){

      if ($(this).data('mainfoo')) return $(this).data('mainfoo');

            var mainfoo = new foo();

      $(this).data('mainfoo', mainfoo);

        });    
};

var myfoo = $('body').mainfoo();
try{
    myfoo.data('mainfoo').bar();
}catch(e){
    console.log(e);
}

Answer 3

two ways

var foo = function(){
    return {
        bar: function(){ alert('bar')}
    };
};
jQuery.fn.mainfoo = function() {
    ///
    var mainfoo = foo();
    ///
};

other way

var foo = function(){
    this.bar = function() {
        alert('bar');
    }
};
$.fn.mainfoo = function() {
    var mainfoo = new foo();  
};