unable to show session message in PHP?

Question

I set session message in my class file like $_SESSION['op_status'] = 'MY MESSAGE HERE'; then redirect the page header("location:news.php"); Page redirects to news.php but session message is not displaying.

config.php:

<?php
   session_start();
   // DATABASE CONFIURATION GOES HERE
?>

news.php:

<?php
  require_once 'config.php';
  require_once 'classes/class.news.php';
  $objNews = new News();

  if(isset($_POST['submit']) && $_POST['submit'] == 'add')
   $objNews->add();

?>

<span class='text-warning'><?php echo $_session['op_status']; ?></span>

class.news.php:

public function add() {
  if(){
     // SOME CODE GOES HERE
  } else {
     $_SESSION['op_status'] == 'Already Exist';
  }
}

Answer 1

You need to use exit() just after header().

 $_SESSION['msg']="Hello";
 header("Location: account.php");
 exit();

then in account.php use

 echo $_SESSION['msg'];

Make sure session_start(); is on every page where you want to show/create session messages.

Instead of using this way, I prefer to use below function. (to distinguish if it was error message or success as in Bootstrap HTML markup)

 function _redirect($url=NULL, $message=NULL, $message_type=NULL){
      $_SESSION['sess_flash_message']= array();
      if($message){
          switch($message_type){ 
            case 'success': $_SESSION['sess_flash_message'][] = '<div class="alert alert-success"><button data-dismiss="alert" class="close" type="button">×</button>'.$message.'</div>';break;
            case 'error': $_SESSION['sess_flash_message'][] = '<div class="alert alert-error"><button data-dismiss="alert" class="close" type="button">×</button>'.$message.'</div>';break;
            case 'notice': $_SESSION['sess_flash_message'][] = '<div class="alert alert-info"><button data-dismiss="alert" class="close" type="button">×</button>'.$message.'</div>';break;
            case 'warning': $_SESSION['sess_flash_message'][] = '<div class="alert alert-block"><button data-dismiss="alert" class="close" type="button">×</button>'.$message.'</div>';break;
            default: $_SESSION['sess_flash_message'][] = $message;
          }
      }
    if($url) {
        header("Location: ".$url);
    } else {
        header("Location: ".$_SERVER['HTTP_REFERER']);
    }
     exit();
     ob_flush();    
}

and call _redirect('login.php','You need to login first!','warning');