在asp.net中加载图片

Question

EDIT

I have a upload result action, it can take minutes for returning a new page. I want to set in a div or something a loading image.

I don't know why but i get the feeling this is not the right way. What is the right way to show a loading screen/add loading image in ASP.NET.

I have this:

    [HttpPost]
    public ActionResult UploadTarget(UploadViewModel model)
      {
    //code that takes minutes
    return RedirectToAction("UploadSuccess", "Upload");
    }

How can i trigger a function before it begins run the uploadtarget function.

<script>
    function wait() {
       document.getElementById("wait").innerHTML = '<img src="/Images/wait.png" alt="Smiley face" height="42" width="42"> ';
    }
</script>

<div class="col-md-6">
     @using (Html.BeginForm("UploadActual", "Upload", FormMethod.Post, new { enctype = "multipart/form-data" })) {
           @Html.AntiForgeryToken()
           @Html.EditorFor(model => model.Remark)
           @Html.ValidationMessageFor(model => model.Remark)
           <input onclick="wait()"type="submit" value="Create" class="btn btn-   primary btn-lg"/>
}
</div>

<div id="wait"class="col-md-6"></div>

It runs my javascript function after the RedirectToaction. So it does nothing anymore. How can i fix this? with c# or javascript? Or is there a other good solution?

Answer 1

You can display the image right away and then submit the form on timeout, to give image time to display. Something like this:

function wait() {
   document.getElementById("wait").innerHTML = '<img src="/Images/wait.png" alt="Smiley face" height="42" width="42"> ';
   setTimeout(function(){document.getElementById("myForm").submit()},10);
}

<input onclick="wait()"type="button" value="Create" class="btn btn-   primary btn-lg"/>

Where "myForm" is ID of your form.