I have encountered a very strange problem. Basically, there is a Delete ActionLink. Once clicked, the code checks the condition, checks true/false, stays on current page or goes to Delete view.

I have posted the solution for this scenario and got some very helpful replies. I worked on it and took it to a situation where I was about to succeed.

Anyway, here are the codes

Index View: AJAX calls the Delete action, returns JSON or EmptyResult. If EmptyResult, then it is a failure as the original ActionLink has been disabled, AJAX will call the error function, which calls another action "Delete2".

<td>
                @Html.ActionLink("Edit", "Edit", new { id = item.CustomerId }, htmlAttributes: new { @class = "mergo-actionlink" }) |
                @Html.ActionLink("Details", "Details", new { id = item.CustomerId }, htmlAttributes: new { @class = "mergo-actionlink" }) |
                @Html.ActionLink("Delete", "Delete", new { id = item.CustomerId }, htmlAttributes: new { @class = "mergo-actionlink-delete", data_value = item.CustomerId })
            </td>
        </tr>
    }

</table>

<script type="text/javascript">
    $('.mergo-actionlink-delete').click(
function () {
    var clickedId = $(this).attr('data-value');
    $.ajax({
        dataType: "json",
        url: '@Url.Action("Delete", "Customers")',
        data: { id: clickedId},
        success: function (data) {
            alert(data.message);
        },
        error: function () {
            alert("EmptyResult returns.");
            debugger;
            $.post('@Url.Action("Delete2", "Customers")', { id: clickedId });
        },
        async: false
    });
    return false;
});
</script>

Controllers:

public ActionResult Delete(Guid? id)
{
    if (id == null)
    {
        return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
    }
    Customer customer = db.Customers.Find(id);
    if (customer == null)
    {
        return HttpNotFound();
    }

    if (customer.Orders.ToList().Count() != 0)
    {
        return Json(new { message = "This customer has order(s) attached." }, "text/plain", JsonRequestBehavior.AllowGet);
    }
    return new EmptyResult();
}

public ActionResult Delete2(Guid? id)
{
    if (id == null)
    {
        return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
    }
    Customer customer = db.Customers.Find(id);
    if (customer == null)
    {
        return HttpNotFound();
    }
    return View(customer);
}

Delete2.cshtml

@model MergoMVC.Customer

@{
    ViewBag.Title = "Delete";
}

<h2>Delete</h2>

<h3>Are you sure you want to delete this?</h3>
<div>
    <h4>Customer</h4>
    <hr />
    <dl class="dl-horizontal">
        <dt>
            @Html.DisplayNameFor(model => model.UserName)
        </dt>

        <dd>
            @Html.DisplayFor(model => model.UserName)
        </dd>

        <dt>
            @Html.DisplayNameFor(model => model.Password)
        </dt>

        <dd>
            @Html.DisplayFor(model => model.Password)
        </dd>

        <dt>
            @Html.DisplayNameFor(model => model.Email)
        </dt>

        <dd>
            @Html.DisplayFor(model => model.Email)
        </dd>

    </dl>

    @using (Html.BeginForm()) {
        @Html.AntiForgeryToken()

        <div class="form-actions no-color">
            <input type="submit" value="Delete" class="btn btn-default" /> |
            @Html.ActionLink("Back to List", "Index")
        </div>
    }
</div>

And I do have Delete.cshtml and Delete2.cshtml views for the actions. The symptom is - from debugging, Visual Studio went into Delete2 action, returned the "customer" to Delete2.cshtml view, executed it from head to toe. But the browser stayed still on index page. I think something is wrong with the return false; in the AJAX. I'm new to this, so I need some help. Thanks.