Not able to retain original values after edit in mvc - asp.net-mvc

Question

i m not able to solve one issue that is , there are two files one is uploaded at the form filled up for the first time and the other file will be uploaded when the form willl be edited , but the issue is that, when the first uploaded file is shown in edit and no changes be made, that files gets blank , i used exclude as well but that does not made any effect.
My Controller methods:
public ActionResult Edit(int? id)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
FileDetails fileDetails = db.FileUpload.Find(id);
if (fileDetails == null)
{
return HttpNotFound();
}
return View(fileDetails);
}
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Edit([Bind(Exclude= "FileBeforeTour,FileBeforeTourName")] FileDetails fileDetails)
{
if (ModelState.IsValid)
{
string uploadedfilename = Path.GetFileName(fileDetails.fileaftertourupload.FileName);
if (!string.IsNullOrEmpty(uploadedfilename))
{
string filenamewithoutextension = Path.GetFileNameWithoutExtension(fileDetails.fileaftertourupload.FileName);
string extension = Path.GetExtension(fileDetails.fileaftertourupload.FileName);
string filename = filenamewithoutextension + DateTime.Now.ToString("yymmssfff") + extension;
fileDetails.FileAfterTourName = filename;
fileDetails.FileAfterTour = "~/Content/Files/" + filename;
filename = Path.Combine(Server.MapPath("~/Content/Files"), filename);
fileDetails.fileaftertourupload.SaveAs(filename);
db.Entry(fileDetails).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Index");
}
}
return View(fileDetails);
}
My Edit View:
#model OnlineStationaryRegister.Models.FileDetails
#{
ViewBag.Title = "Edit";
}
<h2>Edit</h2>
#using (Html.BeginForm("Edit", "File", FormMethod.Post, new { #enctype = "multipart/form-data" }))
{
#Html.AntiForgeryToken()
<div class="form-horizontal">
<h4>FileDetails</h4>
<hr />
#Html.ValidationSummary(true, "", new { #class = "text-danger" })
#Html.HiddenFor(model => model.FileId)
<div class="form-group">
#Html.LabelFor(model => model.Officername, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.Officername, new { htmlAttributes = new { #class = "form-control" } })
#Html.ValidationMessageFor(model => model.Officername, "", new { #class = "text-danger" })
</div>
</div>
<div class="form-group">
#Html.LabelFor(model => model.Designation, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.Designation, new { htmlAttributes = new { #class = "form-control" } })
#Html.ValidationMessageFor(model => model.Designation, "", new { #class = "text-danger" })
</div>
</div>
<div class="form-group">
#Html.LabelFor(model => model.FileBeforeTour, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
View File
</div>
</div>
<div class="form-group">
#Html.LabelFor(model => model.FileAfterTour, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
<input type="file" name="fileaftertourupload" />
</div>
</div>
<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Save" class="btn btn-default" />
</div>
</div>
</div>
}
<div>
#Html.ActionLink("Back to List", "Index")
</div>
#section Scripts {
#Scripts.Render("~/bundles/jqueryval")
}
My FileDetails model:
namespace OnlineStationaryRegister.Models
{
public class FileDetails
{
[Key]
public int FileId { get; set; }
public string Officername { get; set; }
public string Designation { get; set; }
public string FileBeforeTour { get; set; }
public string FileAfterTour { get; set; }
public string FileBeforeTourName { get; set; }
public string FileAfterTourName { get; set; }
public int status { get; set; } = 1;
[NotMapped]
public HttpPostedFileBase filebeforetourupload { get; set; }
[NotMapped]
public HttpPostedFileBase fileaftertourupload { get; set; }
}
}

Answer 1

It can be solved in many ways. One of the simplest ways as follows:
db.Entry(fileDetails).State = EntityState.Modified;
db.Entry(fileDetails).Property(x => x.FileBeforeTourName).IsModified = false; //<-- Here it is
db.Entry(fileDetails).Property(x => x.FileBeforeTour).IsModified = false; //<-- Here it is
db.SaveChanges();