问题
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)
{
Session["FileUpload1"] = FileUploadQ2;
foreach (HttpPostedFile file in FileUploadQ2.PostedFiles)
{
listofuploadedfiles.Text += String.Format("<p><font color='black'>" + file.FileName + "</font><a class='close'><font color='red'>x</font><a>" + "</p>");
}
}
else if (Session["FileUpload1"] != null && (!FileUploadQ2.HasFile))
{
FileUploadQ2 = (FileUpload)Session["FileUpload1"];
}
else if(FileUploadQ2.HasFile)
{
Session["FileUpload1"] = FileUploadQ2;
}
回答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.
来源：https://stackoverflow.com/questions/61655100/file-upload-control-session-does-not-remove-after-remove-file-from-list