使用Linux上运行的.Net 2.2内核读取文件共享上的文件内容

Question

Code below works under windows but get an exception under Linux where the user home drive seems to be prepended to the LocalPath obtained when trying to open the file. Same problem if I use a FileStream.

testing under RHEL 7.6

Does anyone know of a workaround or root cause?

Had to make the actual file share anonymous in snippets below so please ignore any typo in the path, the fact it works on windows is important bit.

Output is:

IsUnc True isFile True LocalPath=\\lnasvr001.partners\dfs\Analytics\suite\demo\externaldata\DemoDataset\temp\diagnose.json AbsolutePath=/dfs/Analytics/suite/demo/externaldata/DemoDataset/temp/diagnose.json

Exception is:

Unhandled Exception: System.IO.FileNotFoundException: Could not find file '/home/appuser/testapp/\\lnasvr001.partners\dfs\Analytics\suite\demo\externaldata\DemoDataset\temp\diagnose.json'.
   at Interop.ThrowExceptionForIoErrno(ErrorInfo errorInfo, String path, Boolean isDirectory, Func`2 errorRewriter)
   at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String path, OpenFlags flags, Int32 mode)
   at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options)
   at System.IO.StreamReader..ctor(String path, Encoding encoding, Boolean detectEncodingFromByteOrderMarks, Int32 bufferSize)
   at System.IO.File.InternalReadAllText(String path, Encoding encoding)
   at System.IO.File.ReadAllText(String path)

My code:

static void Main(string[] args)
    {
        var path = "file://lnasvr001.partners/dfs/Analytics/suite/demo/externaldata/DemoDataset/temp/diagnose.json";
        Uri uri = new Uri(path);
        Console.WriteLine($"IsUnc {uri.IsUnc} isFile {uri.IsFile} LocalPath={uri.LocalPath} AbsolutePath={uri.AbsolutePath}");
        Console.WriteLine($"File Content Length {File.ReadAllText(uri.LocalPath).Length}");
    }

Answer 1

The problem is the way that you build the path

You have to use Path.Combine

static void Main(string[] args)
    {
        //var path = "file://lnasvr001.partners/dfs/Analytics/suite/demo/externaldata/DemoDataset/temp/diagnose.json";
        var path = Path.Combine("file:","lnasvr001.partners/dfs/Analytics/suite/demo/externaldata/DemoDataset/temp/diagnose.json");
        Uri uri = new Uri(path);
        Console.WriteLine($"IsUnc {uri.IsUnc} isFile {uri.IsFile} LocalPath={uri.LocalPath} AbsolutePath={uri.AbsolutePath}");
        Console.WriteLine($"File Content Length {File.ReadAllText(uri.LocalPath).Length}");
    }