javascript - if email exists add option value to dropdown -

i have dropdown wich want populate 1 option if email exists in db. hiding option value , using ajax search if email exists.

$('#email-input').live('change', function() {     //ajax request     $.ajax({         url: "email_check.php",         data: {             'email' : $('#email-input').val()         },         datatype: 'json',         success: function(data) {             if(data.result) {         document.getelementbyid("admdivcheck").style.display = "block";             }             else {         document.getelementbyid("admdivcheck").style.display = "none";             }         },         error: function(data){             //error         }     }); }); 

something not working right. also, if can me change value of string ($total) if email exists, lose 100 value , display final value.

thank in advance