.Net 远程路径权限访问。

先贴下代码，后续写一些分析，和遇到的问题。

 private static string ProcessErrorReadToEnd(Process p)
        {
            string errorString = string.Empty;
            try
            {
                if (p!=null && p.HasExited && p.ExitCode == 2)
                {
                    errorString = p.StandardError.ReadToEnd();
                }
            }
            // catch exception and return empty string, no need to throw exception outside this function.
            catch (Exception ex)
            {
                ConsoleLog.Debug(msg => msg("[ProcessErrorReadToEnd] Error: "+ ex.StackTrace));
            }
            return errorString;
        }

  public static RemoteShareConnectionAttempt TestShare(string path, string username, string password)
        {
            //TODO: what happens if the remote computer rebooted since we set this up? *
            //        we'll need a way to "ping" the share and reconnect 

            if( path == null )
            {
                ConsoleLog.Debug(msg => msg("path is null"));
                throw new System.ArgumentNullException("path");
            }

            if( username == null )
            {
                ConsoleLog.Debug(msg => msg("username is null"));
                throw new System.ArgumentNullException("username");
            }

            if( password == null )
            {
                ConsoleLog.Debug(msg => msg("password is null"));
                throw new System.ArgumentNullException("password");
            }

#if Windows
            try
            {
                string args = "use ";
                if (path.Length != 0)
                {
                    args += """ + path + "" ";

                    if (username.Length == 0)
                    {
                        //[D-01392]
                        //Windows does not let user to connect a share without a username.. 
                        //But if you connect once, it caches the username so you can connect without name.;
                        args += ""/USER:anonymous"";
                    }
                    else
                    {
                        if (password.Length != 0)
                            args += """ + password + "" ";

                        args += ""/USER:" + username + """;
                    }
                }
                else
                {
                    return RemoteShareConnectionAttempt.FAILED;
                }

                //use the Windows/DOS "net" command to connect
                ProcessStartInfo procInfo = new ProcessStartInfo("net ", args);
                
                procInfo.UseShellExecute = false;
                procInfo.RedirectStandardError = true;
                procInfo.RedirectStandardOutput = true;
                procInfo.ErrorDialog = false;
                procInfo.WindowStyle = ProcessWindowStyle.Hidden;

                Process p = Process.Start(procInfo);

                //Give it 90s to connect
                p.WaitForExit(90000);

                ExtendedDirectoryInfo extendedDirectoryInfo = new ExtendedDirectoryInfo(path);

                if (extendedDirectoryInfo.Exists)
                {
                    Core.CoreLog.Info("STR_SHARE_CONNECTED", 0, path, username);
                    return RemoteShareConnectionAttempt.CONNECTED;
                }
                if (p.HasExited)
                {
                    string errorString = ProcessErrorReadToEnd(p);
                    Core.CoreLog.Error("STR_SHARE_CONNECT_FAILED", 0, path, username, p.ExitCode);
                    //if p.HasExited is true and p.ExitCode is 0, it means that the user can logon the server but the folder path is inaccessible or not existing.
                    //if exitcode is 2 and System error 1920 has occurred.It means the file cannot be accessed by the system.
                    //if exitcode is 2 and "System error 53 has occurred.It means the network path was not found.
                    if (p.ExitCode == 0 ||
                        (p.ExitCode == 2 && (errorString.Contains("System error 67") || errorString.Contains("System error 1920") || errorString.Contains("System error 53"))))
                    {
                        return RemoteShareConnectionAttempt.FAILED_INACCESSIBLE_SHARE;
                    }
                    if (p.ExitCode == 2
                        && (errorString.Contains("System error 1219") || string.IsNullOrEmpty(errorString)))
                    {
                        RemoveShareFromWindows(path);
                        return RepeatTestShare(path, username, password);
                    }
                    return RemoteShareConnectionAttempt.FAILED;
                }
                p.Kill();
                p = null;
                Core.CoreLog.Error("STR_SHARE_CONNECT_FAILED", 0, path, username, -2);
                return RemoteShareConnectionAttempt.FAILED;
            }
            catch (Exception ex)
            {
                if (!Core.Closing)
                {
                    Core.CoreLog.Exception(ex, 0);
                    Core.CoreLog.Error("STR_SHARE_CONNECT_FAILED", 0, path, username, -2);
                }
                return RemoteShareConnectionAttempt.FAILED;
            }    
#else
            throw new NotImplementedException("_shareName");
#endif
        }