public static boolean indexExists(Directory directory) throws IOException {String[] files = directory.listAll();String prefix = IndexFileNames.SEGMENTS + "_";for(String file : files) {if (file.startsWith(prefix)) {return true;}}return false;}
public static bool IndexExists(Directory directory){string[] files;try{files = directory.ListAll();} catch (DirectoryNotFoundException nsde) {return false;}if (files != null){string prefix = IndexFileNames.SEGMENTS + "_";foreach (string file in files){if (file.StartsWith(prefix, StringComparison.Ordinal) || file.Equals(IndexFileNames.SEGMENTS_GEN, StringComparison.Ordinal)){return true;}}}return false;}