基于会话的“flash”消息未显示

Question

I'm experiencing an issue with a session message system available here where the messages aren't being displayed. After a lot of trial and error I decided to simplify the issue I was experiencing down to the following for the purposes of testing:

<?php
ini_set('error_reporting', E_ALL);

define('script_access', true);

if (!isset($_SESSION)) {
    session_start();
}

require('../framework/classes/messages.php');

$msg = new Messages();

class Test {
    public $foo;    
    public function __construct() {
        $this->foo = new Messages();
    }
    public function create_form() {
        if (isset($_POST['submit']) == 'Submit') {
            $this->form_process();
        }
        echo '<form action="' . $_SERVER['PHP_SELF'] . '?id=1&table=about" method="post">';
        echo '<input name="submit" type="submit" id="submit" value="Submit">';
        echo '</form>';

    }
    public function form_process() {
        //$new = new Messages();
        $this->foo->add('s', 'new message from');
        header("Location: message.php?proc=true");
    }

}

if ($_GET['proc'] == true) {
    echo 'should be a message here<br>';
    echo $msg->display();
    exit;
} else {
    $test = new Test();
    $test->create_form();
}
?>

After some messing around I added the now commented out $new = new Messages(); to a subroutine and the messages appear. However, leaving it commented out they do not appear. I'm not sure why I have to redeclare a class that I've already declared in the constructor. Does anybody know why this is happening and how I can make it so that I only have to initiate the class in the constructor instead of in the subroutine?

Answer 1

Hmm alright, the issue was it that the class messages initiated inside the test class was only 'living' there:

<?php
ini_set('error_reporting', E_ALL);

define('script_access', true);

if (!isset($_SESSION)) {
    session_start();
}

require('../framework/classes/messages.php');

$msg = new Messages();

class Test {
    public $foo;    
    public function __construct() {
        $this->foo = new Messages();
    }
    public function getmessage() {
        return $this->foo->display();
    }
    public function create_form() {
        if (isset($_POST['submit']) == 'Submit') {
            $this->form_process();
        }
        echo '<form action="' . $_SERVER['PHP_SELF'] . '?id=1&table=about" method="post">';
        echo '<input name="submit" type="submit" id="submit" value="Submit">';
        echo '</form>';

    }
    public function form_process() {
        $this->foo->add('s', 'new message from');
        header("Location: message.php?proc=true");
    }

}

$test = new Test();

if ($_GET['proc'] == true) {
    echo 'should be a message here<br>';
    echo $test->getmessage();
    exit;
} else {

    $test->create_form();
}
?>