Page is not waiting for response from SweetAlert confirmation window

You cannot use this as a drop-in replacement for confirm. confirm blocks the single thread of execution until the dialog has been acknowledged, you cannot produce the same behavior with a JavaScript/DOM-based dialog.

You need to issue a request to /delete.php?id=100 in the success callback for your alert box.

Instead of...

swal("Deleted!", "Your imaginary file has been deleted.", "success");

You need

<a href="#">Delete<a>
...

$.post('/delete.php?id=100').then(function () {
  swal("Deleted!", "Your imaginary file has been deleted.", "success");
});

You also must fix your delete.php to only accept POST requests. It's a huge problem to allow GET requests to delete resources. The first time Google or any other crawler finds your page, it will look at the href of every link in your document and follow each link, deleting all of your content. They will not be stopped by the confirm box, as they probably (with the exception of Google) won't be evaluating any JavaScript.

You can do it this way.

HTML:

<a href="/delete.php?id=100" class="confirmation" >Delete</a>

JS:

$('.confirmation').click(function (e) {
    var href = $(this).attr('href');

    swal({
        title: "Are you sure?",
        type: "warning",
        showCancelButton: true,
        confirmButtonColor: "#DD6B55",
        confirmButtonText: "Yes, delete it!",
        cancelButtonText: "No, cancel plx!",
        closeOnConfirm: true,
        closeOnCancel: true
    },
            function (isConfirm) {
                if (isConfirm) {
                    window.location.href = href;
                }
            });

    return false;
});

Seems a hack but it's working for me.