File Upload Control Session Does Not Remove After Remove File From List

I had frustrated for a few week for this issue, How can I do session for this Multiple File Upload if (Session['FileUpload1'] == null && FileUploadQ2.HasFile) {

Solution 1:

As @VDWWD pointed out, you should not store files in the Session object - store them on disk instead. Below you can find fast implementation of that feature.

    public interface IFileStorage
    {
        Task UploadFile(string fileName, Stream fileContent);
        void TryRemoveFile(string fileName, out bool fileRemoved);
        void GetFile(string fileName);
    }

    public class FileSystemStorage : IFileStorage
    {
        private readonly PhysicalFileProvider _fileProvider;
        private readonly ILogger<FileSystemStorage>_logger;

        public FileSystemStorage(IFileProvider fileProvider, ILogger<FileSystemStorage> logger)
        {
            _fileProvider = (PhysicalFileProvider)fileProvider;
            _logger = logger;
        }

        public void GetFile(string fileName)
        {
            throw new NotImplementedException();
        }

        public void TryRemoveFile(string fileName, out bool fileRemoved)
        {
            try
            {
                RemoveFile(fileName);
                fileRemoved = true;
            }
            catch(Exception ex)
            {
                _logger.LogError($"Couldnt remove file {fileName}: {ex.ToString()}" );
                fileRemoved = false;
            }
        }

        public async Task UploadFile(string fileName, Stream fileContent)
        {
            var filePath = Path.Combine(_fileProvider.Root, fileName);
            if (_fileProvider.GetFileInfo(filePath).Exists)
                throw new ArgumentException("Given file already exists!");

            _logger.LogInformation($"Saving file to: {filePath}..");
            using (Stream file = File.Create(filePath))
            {
                await fileContent.CopyToAsync(file);
                file.Flush();
            }

            _logger.LogInformation($"File: {filePath} saved successfully.");
        }
    }

In Startup.cs, ConfigureServices method add below lines to inject FileSystemStorage:

IFileProvider physicalProvider = new PhysicalFileProvider(Path.Combine(Directory.GetCurrentDirectory(), "AppData"));
services.AddSingleton<IFileProvider>(physicalProvider);
services.AddTransient<IFileStorage, FileSystemStorage>();

Then in your controller constructor obtain the FileSystemStorage instance.