getJSON in CI problem

[eluser]Mitja B.[/eluser]

Code:

$izb = $_GET['izb'];
switch($izb)
{
    
case $izb :    
    $sql = $db -> select("SELECT * FROM " . DB_PREDPONA . "lastminute_mesta WHERE drzava= '".$_GET['izb']."'");
    while ($row = $sql ->fetchrow())
    {    
        $id = $row['id'];
        $ime = $row['mesto'];
        $array[$id] = $ime;
    }
    break;
}

echo json_encode($array);

Code:

/* getJSON */
function spremeniVrednost()
{
    $.getJSON("ajax.php",
      { izb: $("#select1").val()},
      function(json){
          $("#select2").removeOption(/./);
        $("#select2").addOption(json);
        }
    );
}

how can i import this in CI. I have no idea how tu use getJSON in CI.