javascript:show alert if not match

Question

dear all..i have a textfield. i want after i have typed identity number inside it, the script can identifying to "user table" at DB. i want if id number not match can show an alert.. how do i do that?i'm newbie at javascript

Answer 1

Your JS code should be something like this:

var identityNum = 'xxxxx'; // ajdust value / fetch from db
var val = document.getElementById('input-field-id').value;

if (val === identityNum)
{
  // success... your further code
}
else
{
   alert('No match found !!');
}

Answer 2

so basicly you can split up your problem in two parts:

1. on the change of your identity field check the user id

   $('input#userid').change(function(){ checkUserId( $(this).val() ); });
   

2. by checking the database

   function checkUserId( id ){
       $.ajax({
           type: 'POST', // or get
           url: 'some_url.php',
           data: {userid:id},
           success: function(data){
               if(data == 'false') alert('Wrong user id');
           }
       });
   }
   

   someting like that