jquery - How to pass variables to a function and return some of their properties javascript -

i have drop down menu , when select element want see list of information element. drop down , selection work since have lot of options (more showing) try make function return information element selected don't repeat code. function give me error message:"cannot read property 'top_1' of undefined" console.log(obj.top_1) works fine.

var obj = {   top_1 :"bla",   top_2 :"bla bla",   objdetail_1 :{ top_1 :"bli",             top_2 :"bli bli",             name1:"aaa",             name2:"aaaa"             },   objdetail_2 :{ top_1 :"blo",             top_2 :"bli blo",             name1:"bbb",             name2:"bbbbb"             }            };  $(document).ready(function() {   $('.mystuff li ul li').click( function(event){     $(document).find('#description').css('visibility', 'visible');     var idelement = $(this).attr('id');      if (idelement == 'top_1'){             console.log(obj.top_1);             ing(obj, top_1);     };      function ing(element1, element2){         console.log(element1.top_1 +" "+ element1.top_2 +" "+element1.element2.top_1+" "+ element1.element2.top_2);     };   }); });  

thank help!

you pass element2 string , replace objdetail_1 this:

ing(obj, "objdetail_1"); 

then in function body access properties this:

function ing(element1, element2){   console.log(element1.top_1, element1.top_2,     element1[element2].top_1, element1[element2].top_2); };