manage_cart.php

<?php
session_start();
if($_SERVER["REQUEST_METHOD"]=="POST")
{
    if(isset($_POST['Add_To_Cart']))
    {
        if(isset($_SESSION['cart']))
        {
            $myitems=array_column($_SESSION['cart'], 'Item_Name');
            if(in_array($_POST['Item_Name'], $myitems))
            {
                echo
                    ("<script>
                    alert('Item Is Already Added');
                    window.location.href='index.php';
                    </script>");
            }
            else
            {
            $count= count($_SESSION['cart']);
            $_SESSION['cart'][$count]=array('Item_Name'=> $_POST['Item_Name'], 'Price'=> $_POST['Price'], 'Quantity'=>1);
            echo
            ("<script>
            alert('Item Added');
            window.location.href='index.php';
            </script>");
            }
        }
        else
        {
            $_SESSION['cart'][0]=array('Item_Name'=> $_POST['Item_Name'], 'Price'=> $_POST['Price'], 'Quantity'=>1);
            echo
                    ("<script>
                    alert('Item Added');
                    window.location.href='index.php';
                    </script>");
        }
    }

    if(isset($_POST['Remove_Item']))
    {
        foreach($_SESSION['cart'] as $key => $value)
        {
            if($value['Item_Name']== $_POST['Item_Name'])
            {
                unset($_SESSION['cart'][$key]);
                $_SESSION['cart']=array_values($_SESSION['cart']);
                echo"
                <script>
                alert('Item Removed');
                window.location.href='shoppingcart.php';
                </script>";
            }
        }
    }

}
?>