How to fix InputStream ReadTimeout error on FileUpload

Question

My setup: asp.net mvc web app with a simple email form with fileUpload and send button.

The email is sent correctly and files are attached - but the attachments are empty. Debugging the controller gives an InputStream.ReadTimeout in the expression var myFiles = model.MyFiles; (see below controller code).

Model (only parts)

public List<HttpPostedFileBase> MyFiles { get; set; }
public List<EmailAttachments> Attachments { get; set; }

HTML

<form id="data" method="post" enctype="multipart/form-data">
    <input id="files" type="file" aria-label="files" multiple="multiple" name="MyFiles">
</form>

<input type="button" class="btn k-button k-primary" id="send" value="Send" />

Javascript

 $(function () {

    $("#send").click(function () {
         var form = $("#data");
         var formData = new FormData(form[0]);

         var files = form.find("#files")[0].files;

         $.each(files, function() {
           var file = $(this);
           formData.append(file[0].name, file[0]);
         });

         $.ajax({
             type: "POST",
             url: url,
             data: formData,
             contentType: false,
             processData: false,
             success: function (response) {
                 alert("Success");
             },
             error: function (response) {
                 alert("Error");
             }
         });

    });

Controller

[HttpPost]
public ActionResult SendCompanyEmail(GeneralEmailViewModel model)
{
    ...
    var myFiles = model.MyFiles; // here occurs the ReadTimeout
    if (myFiles != null)
    {
        foreach (var file in myFiles)
        {
            if (file != null && file.ContentLength > 0)
            {
                MemoryStream stream = new MemoryStream(file.ContentLength);
                stream.Position = 0;
                attachements.Add(new EmailAttachments
                {
                    FileName = file.FileName,
                    ContentType = file.ContentType,
                    Stream = stream,
                });
            }
        }
    }
// ... code for sending the email ...
}

Any suggestions where the cause for the ReadTimeout could be and how to fix it?

Answer 1

The controller code for building the attachments was faulty. I found a working code:

    if (myFiles != null)
    {
        foreach (var file in myFiles)
        {
            if (file != null && file.ContentLength > 0)
            {
                //MemoryStream stream = new MemoryStream(file.ContentLength);
                //stream.Position = 0;
                attachements.Add(new EmailAttachments
                {
                    FileName = file.FileName,
                    ContentType = file.ContentType,
                    Stream = file.InputStream
                });

            }
        }
    }

The InputStream.ReadTimeout message still can be read out when debugging the controller. Whether this is just a futile message of no consequence I could not figure out.

Anyway, the approach as outlined in my original post with the correction given above works properly for uploading files and converting them to email attachments.