Html correct filePath for downloading file from Server

Question

I have done the function to save a file to a Folder in Server, **I am now trying to get the file back from Server by using HTML download, but haven't found the way to get the correct filepath yet.

After stored a file in a Folder in Server, saved filePath in DB by using Entity Framework, I retrieved file from DB with filePath = /VisitReportAttachments/1ea2b64e-545d-4c50-ae7d-eefa7178d310.png. But this filePath doesn't work right.

 <a href="@file.Path" download="@file.name">Click here to download</a>
//file.Path = /VisitReportAttachments/1ea2b64e-545d-4c50-ae7d-eefa7178d310.png

I got an error: Failed - No file

Take a look at create FilePath path in SaveFile code in Controller:

private void SaveFile(HttpPostedFileBase file)
{
    string serverPath = "\\VisitReportAttachments";
      if (file!= null)
        {
        if (!Directory.Exists(serverPath))
        {
            Directory.CreateDirectory(serverPath);
        }
         var fileName = Guid.NewGuid()+ Path.GetExtension(file.FileName);
         var path = Path.Combine("\\", new DirectoryInfo(serverPath).Name, fileName);
         path = relativePath.Replace(@"\", "/"); //this path is stored to DB
          ....
       //As I mentioned: save file to Server is done. I simply post the code that create the filepath in SQL DB while file is storing to Server*
        }
}

FilePath is stored in DB like: /VisitReportAttachments/1ea2b64e-545d-4c50-ae7d-eefa7178d310.png

Need help!

Answer 1

Found out the solution by using Server.MapPath to Map the filePath to the correct Path.

Instead of using downloadable Link in HTML View, I create Download function in Controller:

[HttpPost]
        [Authorize]
        public ActionResult DownloadAttachment()
        {
            return Json(true);
        }

        [HttpGet]
        public ActionResult Download(Guid? attachmentId)
        {
            var visitAttachment = _visitAttachmentService.FindOne(x => x.Id == attachmentId);
            try
            {
                var serverPath = Server.MapPath(visitAttachment.Path);
                byte[] fileBytes = System.IO.File.ReadAllBytes(serverPath);
                return File(fileBytes, System.Net.Mime.MediaTypeNames.Application.Octet, visitAttachment.AttachmentName);

            }
            catch
            {
                return File(Encoding.UTF8.GetBytes(""), System.Net.Mime.MediaTypeNames.Application.Octet, visitAttachment.AttachmentName);
            }

        }

Call this method in View:

<a href="" onclick="Download('@file.Id');">@file.AttachmentName</a>

<script>
    function Download(attachmentId) {
            var url = '/Visits/DownloadAttachment';
            $.post(url,
                {
                    //                  FilePath: filePath
                },
                function (data) {
                    var response = JSON.parse(data);
                    window.location = '/Visits/Download?attachmentId=' + attachmentId;
                },
                "json");
        }
    </script>

It works perfectly now.

Answer 2

Your private string SaveFile(HttpPostedFileBase file) method should return a NewFile model object that reflects the entity in your database. private NewFile SaveFile(HttpPostedFileBase file)

public class NewFile
{
   public int NewFileId { get; set; } 
   public string FileName { get; set; }
   public string FilePath { get; set; }
}

You will need do something similar to the following code when you save the File:

using (var db = new YourDbContext())
{
   var newFile = new NewFile { FileName = fileName, FilePath = path };

   var savedFile = db.Add(newFile);

   db.SaveChanges();

   return savedFile;   // here is the object you can return to the view and access 
                       // its properties
}

Answer 3

    private string SaveFile(HttpPostedFileBase file)
    {
        if (file == null)
            return string.Empty;

        string saveFolder = "VisitReportAttachments";

        string fileName = fileName = Guid.NewGuid() + Path.GetExtension(file.FileName);
        string serverFolderPath = AppDomain.CurrentDomain.BaseDirectory + "/" + saveFolder;
        string savePath = serverFolderPath + "/" + fileName;


        if (!Directory.Exists(serverFolderPath))
            Directory.CreateDirectory(serverFolderPath);

        file.SaveAs(savePath);

        return Url.Content($"~/{saveFolder}/{fileName}");
    }

Answer 4

You have not shored file in folder. Add below line in code

file.SaveAs(serverPath + file.FileName);

So your C# code will be like

private string SaveFile(HttpPostedFileBase file)
{
    string serverPath = "\\VisitReportAttachments";
      if (file!= null)
        {
        if (!Directory.Exists(serverPath))
        {
            Directory.CreateDirectory(serverPath);
        }
         var fileName = Guid.NewGuid()+ Path.GetExtension(file.FileName);
         var path = Path.Combine("\\", new DirectoryInfo(serverPath).Name, fileName);

         file.SaveAs(serverPath + file.FileName);

         path = relativePath.Replace(@"\", "/");

         return path;
        }
         return string.Empty;
}