PHP未设置会话不起作用

Question

My PHP script to unset session variable is not working.

I need to call a PHP file destroy.php which contains code to unset session variable from ajax, everything is working fine except session clear.

I'm posting my code for clearing session variable, please point out my error.

jQuery Code:

$.ajax
                    ({
                        type: "POST",
                        url: "SubmitReview.php",
                        data: dataString,
                        cache: false,

                        success: function(response)
                        {
                            $.fn.destroySession();
                            $('body').animate({scrollTop:0}, 500);
                            $('body').children(':not(div.ErrorMessageContainer)').fadeTo(500, 0.1);
                            $('div.ErrorMessageContainer').html(response).fadeIn(500).delay(5000).fadeOut(500);
                            setTimeout(function()
                            {
                                $('body').children(':not(div.ErrorMessageContainer)').fadeTo(500, 1);
                            }, 5400);
                            setTimeout(function()
                            {
                                window.location.href = "Thanks.php";
                            }, 5600);
                        }
                    });

$.fn.destroySession = function()
            {
                $.post("Destroy.php");
            }

destroy.php:

<?php

if(isset($_SESSION['MN']))
{
    $_SESSION['MN'] = array();
    unset($_SESSION['MN']);
}

?>

Answer 1

Put session_start() on first line.

<?php
session_start();

if(isset($_SESSION['MN']))
{
    $_SESSION['MN'] = array();
    unset($_SESSION['MN']);
}