public VirtualFileProvider(
     IOptions <XqVirtualFileSystemOptions> options,
     IDynamicFileProvider dynamicFileProvider)
 {
     _options      = options.Value;
     _fileProvider = CreateProvider(dynamicFileProvider);
 }
 public InternalVirtualFileProvider(XqVirtualFileSystemOptions options)
 {
     _options = options;
     _files   = new Lazy <Dictionary <string, IFileInfo> >(
         CreateFiles,
         true
         );
 }