Peringatan : Kunci array "crud" yang tidak ditentukan pada baris 91

code line 91 :

<?php if($_GET['crud'] == 'true'):?>

Full Code :

<?php if($_GET['crud'] == 'true'):?>
    <script type="text/javascript">
        var title = "<?php echo $_GET['title']?>";
        var msg = "<?php echo $_GET['msg']?>";
        var type = "<?php echo $_GET['type']?>";
        $.toast({
             heading: title,
             text: msg,
             position: 'top-right',
             loaderBg: '#fff',
             icon: type,
             hideAfter: 3500,
             stack: 6
         })
    </script>
    <?php endif; ?>