会话开始无效

Question

Can Someone help me? Session start doesn't work. What Am I doing wrong? The error message is Fatal error: Uncaught Error: Call to a member function increment_index() on null

This is my index.php

<?php

require 'config/bootstrap.php';

get_header();

$_SESSION = get_session_start_values();

dd($_SESSION['quiz']->increment_index());

render_fragment( 'quiz' );

get_footer();

This is my bootstrap file

<?php
session_start();
require 'quiz.php';
require 'helpers.php';
require 'database.php';

And in my helpers I'm using this:

function get_session_start_values() {
    if ( ! isset( $_SESSION['quiz'] ) ) {
        return  [
            'quiz' => new Quiz(),
            'yes_no_questions' => 'yes_no_questions',
            'end_game' => false
        ];
    }
}

Answer 1

It would only work once because of this line:

if ( ! isset( $_SESSION['quiz'] ) ) {

Second time around,

$_SESSION = get_session_start_values();

sets $_SESSION to null

This should fix it:

function get_session_start_values() {
    if ( ! isset( $_SESSION['quiz'] ) ) {
        return  [
            'quiz' => new Quiz(),
            'yes_no_questions' => 'yes_no_questions',
            'end_game' => false
        ];
    }
    return $_SESSION;
}

Answer 2

$_SESSION is a super-global. that is, you can just use it everywhere to access the session. this includes the function where you set-up the initial values of the session:

function get_session_start_values() {
    if ( ! isset( $_SESSION['quiz'] ) ) {
        return  [
            'quiz' => new Quiz(),
            'yes_no_questions' => 'yes_no_questions',
            'end_game' => false
        ];
    }
}

Instead of asking for start values, just initialize if needed:

function init_session_values(): void {
    if ( ! isset( $_SESSION['quiz'] ) ) {
        $_SESSION['quiz'] = new Quiz();
    }
    ...
}

Then just call the function when you mean it. you don't need to take care of any return values.

<?php

require 'config/bootstrap.php';

init_session_values();

get_header();

This is much more straight forward to use and for what $_SESSION is made for (easy superglobal access).