Upload validation

[Stephen]

Hello,

I'm using the upload control in async mode and am passing back the empty string to signify success from my post routine.  I need to validate that the file extensions and file size are within certain specs when files are uploaded.  I have seen posts about handling this in jquery and using an alert to display the message but a) I prefer not to use alerts and b) it shows the alert but still goes to the post method (even with the e.preventDefault in place).

I would prefer to do the checks in the post method and return a string that I can display so it would look like my usual validation.  I know that the empty string  signifies success and anything else signifies failure but when I try to trap this in onError it doesn't capture it.  I'm sure there is a way to do this but I am missing something.

Here is my view:

@model PASS.ViewModels.Proposals.AttachmentsViewModel

<div class="editor-container">

    @Html.Hidden("Form_Disabled", ViewData["FormDisabled"])

    <p>File uploads can not exceed 1MB each and must be of the following file types: pdf, jpg, gif, png.</p>

    <div class="editor-label">
        @Html.Label("File(s):")
    </div>
    <div class="editor-field">
        @(Html.Kendo().Upload()
            .Name("Upload")
            .Async(async => async
                .Save("AddAttachments", "Proposals", new { proposalID = Model.Proposal_ID })
            )
        )
    </div>
    <br class="clear" />
    <br />
    <br />

    @(Html.Kendo().Grid<PASS.ViewModels.Proposals.AttachmentsViewModel>()
        .Name("Attachments")
        .Columns(columns =>
        {
            columns.Bound(c => c.File_Name).ClientTemplate("<a href='" + Url.Action("LoadAttachment", "Proposals") + "/#= ID #'>" + "#= File_Name #" + "</a>").Title("File Name");
            columns.Bound(c => c.File_Size).Title("Size");
            columns.Bound(c => c.Content_Type).Title("Type");
            columns.Command(command => { command.Destroy(); }).Width(90);
        })
        .Sortable()
        .DataSource(dataSource => dataSource
            .Ajax()
            .Model(model => model.Id(c => c.ID))
            .Read(read => read.Action("GetAttachments", "Proposals", new { proposalID = Model.Proposal_ID }))
            .Destroy(destroy => destroy.Action("DeleteAttachment", "Proposals"))
        )
    )

    <br />
    <p>Upoaded files will not be available for viewing until they have been reviewed.</p>

</div>

<script type="text/javascript">
$(document).ready(function () {
    var formDisabled = $('#Form_Disabled').val();
    if (formDisabled == "True") {
        $('#Upload').data('kendoUpload').disable();
        $('#Attachments').data('kendoGrid').bind("dataBound", function () {
            $('.k-grid-delete', '#Attachments').hide();
        })
    }

    $('#Upload').data('kendoUpload').bind("success", function () {
        $('#Attachments').data('kendoGrid').dataSource.read();
    })
});
</script>

Here is my post method:

[HttpPost]
public ActionResult AddAttachments(int proposalID, IEnumerable<HttpPostedFileBase> upload)
{
    int user_id = Convert.ToInt32(((Claim)((ClaimsIdentity)Thread.CurrentPrincipal.Identity).FindFirst(a => a.Type.Equals("UserID"))).Value);
    var return_message = "";

    if (CheckProposalReadAccess(user_id, proposalID))
    {
        using (var context = new PASSEntities())
        {
            foreach (var file in upload)
            {
                if (Path.GetExtension(file.FileName) != ".pdf" || Path.GetExtension(file.FileName) != ".jpg" || Path.GetExtension(file.FileName) != ".gif" || Path.GetExtension(file.FileName) != ".png")
                {
                    return_message = "Uploads must be one of the following file types: pdf, jpg, gif, png.";
                    break;
                }

                if (file.ContentLength > 1024)
                {
                    return_message = "Uploads can not be larger than 1MB each.";
                    break;
                }

                Proposal_Attachments model = new Proposal_Attachments()
                {
                    Proposal_ID = proposalID,
                    Upload_Date = DateTime.Now,
                    File_Name = Path.GetFileName(file.FileName),
                    File_Size = file.ContentLength,
                    Content_Type = file.ContentType,
                    File_Contents = new byte[file.ContentLength],
                };

                file.InputStream.Read(model.File_Contents, 0, file.ContentLength);

                context.Proposal_Attachments.Add(model);
                context.SaveChanges();
            }

            return Content(return_message);
        }
    }
    else
    {
        return RedirectToAction("Index");
    }
}

Thanks!

[Dimiter Madjarov]

Hello Stephen,


Indeed if a non-empty content is returned from the save handler, the error event of the Upload widget will be triggered. You could access it through the e.XMLHttpRequest parameter.
E.g.

public ActionResult Save(IEnumerable<HttpPostedFileBase> files)
{
    ...
    return Content("my error");
}

function error(e) {
    var response = e.XMLHttpRequest.responseText;
}

Let me know if this was the information that you were looking for.

Regards,
Dimiter Madjarov
Telerik

 

 

[Stephen]

That's exactly what I was looking for!  Thanks!

[Dimiter Madjarov]

Hello Stephen,


I am glad that the issue is resolved.
Do not hesitate to contact us again if further problems arise.

I wish you a great day!

Regards,
Dimiter Madjarov
Telerik