jquery - unable to push values into global array inside $.post() method -

i trying push returned data $.post method global array...please me how return entire array

var retval =[]; function returnoptionlist(optname){    $.post('getlisttypes',{"key":optname},function(data) {      if (data.listnames == optname){          for(var i=0; i<data.values.length;i++){                  retval.push(data.values[i]);         }        }       });    return retval;        } 

use callbacks return data ajax call, not return

function returnoptionlist(optname, callback){     $.post('getlisttypes',{"key":optname},function(data) {          if (data.listnames == optname){              for(var i=0; i<data.values.length;i++){                   retval.push(data.values[i]);             }          }          callback(retval)     });        } 

and call:

returnoptionlist(optname, data) {     console.log(data); //your array })