ASP.NET FileUpload无法访问已关闭的文件

我知道在SO上还有其他几个这样的问题，但是到目前为止，我从一系列网站，SO, MSDN等尝试过的每个答案都证明对错误没有影响。

我有一个asp:FileUpload，在变化，我存储在一个会话变量(我有其他字段，导致post回所以需要确保我有文件的用户上传到某个地方)。

我得到的错误是

{"Cannot access a closed file."}
Data: {System.Collections.ListDictionaryInternal}
HResult: -2146232798
HelpLink: null
InnerException: null
Message: "Cannot access a closed file."
ObjectName: ""
Source: "mscorlib"
StackTrace: "   at System.IO.__Error.FileNotOpen()'r'n   at System.IO.FileStream.Seek(Int64 offset, SeekOrigin origin)'r'n   at System.Web.HttpRawUploadedContent.TempFile.GetBytes(Int32 offset, Int32 length, Byte[] buffer, Int32 bufferOffset)'r'n   at System.Web.HttpRawUploadedContent.CopyBytes(Int32 offset, Byte[] buffer, Int32 bufferOffset, Int32 length)'r'n   at System.Web.HttpInputStream.Read(Byte[] buffer, Int32 offset, Int32 count)'r'n   at GCSearchPortal.GlobalFunctions.UploadFile[T](HttpServerUtility server, FileType type, T file, Int32 id) in C:''Users''zach.ross-clyne''Source''Workspaces''GC Search Portal''GCSearchPortal''GCSearchPortal''GlobalFunctions.cs:line 241"
TargetSite: {Void FileNotOpen()}

这就是我的网页。

system.web部分中的配置

<httpRuntime useFullyQualifiedRedirectUrl="true" maxRequestLength="1048576" requestLengthDiskThreshold="1073741824"/>

导致这个问题的代码是:

internal static int UploadFile<T>(HttpServerUtility server, FileType type, T file, int id)
{
    if (typeof(T) == typeof(HtmlInputFile) || typeof(T) == typeof(FileUpload))
    {
        string fileName = null;
        string location = null;
        dynamic fileUpload = file;
        if (fileUpload.PostedFile != null && fileUpload.PostedFile.ContentLength > 0)
        {
            try
            {
                /* Get a reference to PostedFile object */
                HttpPostedFile attFile = fileUpload.PostedFile;
                /* Get size of the file */
                int attachFileLength = attFile.ContentLength;
                /* Make sure the size of the file is > 0  */
                if (attachFileLength > 0)
                {
                    if (attachFileLength < 52428800)
                    {
                        /* Get extension for file */
                        string ext = Path.GetExtension(attFile.FileName);
                        switch (type)
                        {
                            case FileType.TermsOfBusiness:
                                location = "~/Clients/" + id + "/";
                                fileName = "TOB";
                                break;
                            case FileType.TermsOfRole:
                                location = "~/Jobs/" + id + "/";
                                fileName = "TOR";
                                break;
                            case FileType.CandidateCV:
                                location = "~/Candidates/" + id + "/";
                                fileName = "CV";
                                break;
                            case FileType.NewCV:
                                location = "~/CVs/";
                                fileName = id.ToString();
                                break;
                        }
                        fileName += ext;
                        /* Save the file on the server */
                        System.IO.Directory.CreateDirectory(server.MapPath(location));
                        string filePath = attFile.FileName;
                        string fileName2 = fileUpload.FileName;
                        Stream fStream = fileUpload.FileContent;
                        byte[] contents = new byte[fStream.Length];
                        fStream.Read(contents, 0, (int)fStream.Length); // <<<<< This line causes the crash
                        File.WriteAllBytes(server.MapPath(location + fileName), contents);
                        // This is what the code was at the very beginning before all my changes
                        //attFile.SaveAs(server.MapPath(location + fileName));
                        return 2;
                    }
                    else
                    {
                        return 3;
                    }
                }
                else
                {
                    return 1;
                }
            }
            catch (Exception ex)
            {
                return 1; // <<<<< This is where it's crashing and giving the error above
            }
        }
        else
        {
            return 0;
        }
    }
    else
    {
        throw new Exception("Passed type is not supported");
    }
}

感谢您的帮助

int fileLength = attFile.ContentLength;
byte[] byteContent = new byte[fileLength];
attFile.InputStream.Read(byteContent, 0, iLength);
using (var memStream = new MemoryStream(byteContent))
{
    System.IO.File.WriteAllBytes(server.MapPath(location + fileName), memStream .ToArray());
}