c# - 进程无法访问该文件，因为它正在被另一个进程在第二次调用时使用

Question

我有一个 Azure 函数 (HttpTrigger)，它在我的 Azure 存储中创建一个 tar.gz 文件。

当我触发一次时，文件就成功创建了。但如果我再次点击它，我就会出错:

[Info] The process cannot access the file 'D:\local\Temp\myDir\tarArchive.tar.gz' because it is being used by another process.

我必须重新启动 Azure 门户中的功能才能创建另一个文件。

这是我的代码:

FileStream fs = new FileStream(myDir+"/firstFile", FileMode.Create);
fs.Write(bytesToCompress, 0, bytesToCompress.Length);
fs.Dispose();
FileStream sfs = new FileStream(myDir + "/secondfile", FileMode.Create);
sfs.Dispose();

DirectoryInfo DirectoryOfFilesToBeTarred = new DirectoryInfo(myDir);
FileInfo[] filesInDirectory = DirectoryOfFilesToBeTarred.GetFiles();

string tarArchiveName = myDir + "/tarArchive.tar.gz";

using (Stream targetStream = new GZipOutputStream(File.Create(tarArchiveName)))
 {
    using (TarArchive tarArchive = TarArchive.CreateOutputTarArchive(targetStream, TarBuffer.DefaultBlockFactor))
    {
        foreach(FileInfo fileToBeTarred in filesInDirectory)
        {
           log.Info(fileToBeTarred.FullName);
           TarEntry entry = TarEntry.CreateEntryFromFile(fileToBeTarred.FullName);                            
           tarArchive.WriteEntry(entry, true); // Error thrown here

        }
    }
 }

我认为再次调用该函数时 fileToBeTarred 仍在使用中(我错了吗？)但我已尝试从此 FileInfo 创建一个流以便 Dispose() 它，但没有解决我的问题。我也试过 Delete() 它，但没有任何效果。

有人看到了我没看到的东西吗？

谢谢你的帮助

更新

这是 Wim Coenen 给出的修正代码

using (Stream fileStream = File.Create(tarArchiveName))
using (Stream targetStream = new GZipOutputStream(fileStream))
using (TarArchive tarArchive = TarArchive.CreateOutputTarArchive(targetStream, TarBuffer.DefaultBlockFactor))
 {
   foreach (FileInfo fileToBeTarred in filesInDirectory)
   {
     log.Info(fileToBeTarred.FullName);
     TarEntry entry = TarEntry.CreateEntryFromFile(fileToBeTarred.FullName);
     tarArchive.WriteEntry(entry, true); // Error thrown here 
   }
}

以及错误日志(e = Exception 对象)e.message =>

2018-08-01T11:59:46.887 [Info] The process cannot access the file 'D:\local\Temp\myDir\tarArchive.tar.gz' because it is being used by another process.

e.ToString() =>

2018-08-01T11:59:47.152 [Info] System.IO.IOException: The process cannot access the file 'D:\local\Temp\myDir\tarArchive.tar.gz' because it is being used by another process.

at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)

at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)

at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share)

at ICSharpCode.SharpZipLib.Tar.TarArchive.WriteEntryCore(TarEntry sourceEntry, Boolean recurse)

at ICSharpCode.SharpZipLib.Tar.TarArchive.WriteEntry(TarEntry sourceEntry, Boolean recurse)

at UploadFileFromBCText.Function1.d__4.MoveNext()

Answer 1

看起来您不是在 Azure 存储中创建它，而是在 Function App 实例的本地磁盘上创建它。这可能不是一个好主意，因为实例是短暂的，不会长期保留您的文件。

相反，请查看 Azure Blob Storage Output binding - 它的目的是在不使用低级文件 API 或 SDK 的情况下将文件存储在 Azure 存储中。