根据扩展名对文件排序代码，扩展名排序代码,Erlangdirlis

根据扩展名对文件排序代码，扩展名排序代码,Erlangdirlis

Erlang

dirlist_by_extension(Dir) ->    case file:list_dir(Dir) of        {ok, Filenames} ->            F = fun(Name) ->                    Ext = string:to_lower(filename:extension(Name)),                    {Ext, Name}                end,            List = lists:sort(lists:map(F, Filenames)),            [Name || {_, Name} <- List];        {error, enoent} ->            io:format("The directory(~s) does not exist.~n", [Dir]),            ng    end.

Java

import java.io.*;import java.util.Arrays;import java.util.ArrayList;import java.util.List;import java.util.Comparator;public class FileUtils{  /**   * returns a folder content sorted by extension   * case-insensitive ,ascending order   * subfolders are not included   * @param folder  folder name   * @return     * @throws IOException  if not a folder or not found   */  @SuppressWarnings("unchecked")  public static File[] dirListByExtension(File folder) throws IOException {    if (!folder.isDirectory() || !folder.exists()) {      throw new IOException( folder.getName() + " : Not a folder or not exist");    }    File files[] = FileUtils.list(folder, false); // don't include subfolder    Arrays.sort(files, new Comparator() {      public int compare(final Object o1, final Object o2) {          String s1 = ((File) o1).getName().toLowerCase();          String s2 = ((File) o2).getName().toLowerCase();          final int s1Dot = s1.lastIndexOf('.');          final int s2Dot = s2.lastIndexOf('.');          //           if ((s1Dot == -1) == (s2Dot == -1)) { // both or neither              s1 = s1.substring(s1Dot + 1);              s2 = s2.substring(s2Dot + 1);              return s1.compareTo(s2);          } else if (s1Dot == -1) { // only s2 has an extension, so s1 goes first              return -1;          } else { // only s1 has an extension, so s1 goes second              return 1;          }      }    });   return files;  }    /**   * returns the content of a folder with subfolders included or not   * @param folder   folder name   * @param includeSubFolder  true/false   * @return  array of files   */  public static File[] list(File folder, boolean includeSubFolder) {    if (!folder.isDirectory()) {      return null;    }    File files[] = folder.listFiles();    List<File> list = new ArrayList<File>();    for (File file : files) {      if (file.isDirectory()) {        if (includeSubFolder) {          list.add(file);          }      }      else {       list.add(file);      }    }    if (list.isEmpty()) {      return null;    }    return list.toArray(new File[]{});  }  /*   * TEST   */  public static void main(String args[]) throws Exception {    File files[] = FileUtils.dirListByExtension(new File("C:/temp"));    for (File file : files) {      System.out.println(file.getName());    }    // to reverse    //   List<File> temp = Arrays.asList(files);    //   java.util.Collections.reverse(temp);    //   files = temp.toArray(new File[]{});    //   for (File file : files) {    ///     System.out.println(file.getName());    //   }  }}

Take a look at this HowToto filter by a date interval. Take a look at thisHowTo to sort thefilenames in ascending/descending order (based on the last modifiedtimestamp).

Ruby

def dirlist_by_extension(dirname)  Dir.chdir(dirname) do |dir|    files = Dir.entries('.')    i = 0    files.sort_by{|fname| [File.extname(fname).downcase, i+=1]}  endendfiles = dirlist_by_extension('/')files.each do |file|  puts fileend