$strSQL = "SELECT * FROM v_studentmail WHERE student_code_status = 1 GROUP BY CurLevel CurLevel =$CurLevel ";

$objDB = mssql_select_db("Nitchpon");
 if(isset($_POST['id'])){
     $id= $_POST['id'];
    $CurLevel = iconv('UTF-8','TIS-620',$id);
    $strSQL = "SELECT * FROM v_studentmail WHERE student_code_status = '1' GROUP BY CurLevel  CurLevel ='$CurLevel' ";
    $objQuery = mssql_query($strSQL) or die ("Error Query [".$strSQL."]");
    $mail_to='';
    while($objResult = mssql_fetch_array($objQuery)){
        $mail_to = $mail_to.$objResult["Mail1"].'@'.$objResult["WebMail1"].',';
    }
    $new_row['email']=$mail_to;
    $row_set = $new_row;
    
    echo json_encode($row_set);
 }