C#将指定目录所有文件名转换成小写的方法

本文实例讲述了C#将指定目录所有文件名转换成小写的方法。分享给大家供大家参考。具体如下：

using System;
using System.IO;
using System.Linq;
namespace RobvanderWoude
{
class LoCase
{
 static int Main( string[] args )
 {
  string dir = string.Empty;
  string filespec = string.Empty;
  char[] trailingbackslash = "\\".ToCharArray( 0, 1 );
  char[] upcaseletters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray( 0, 26 );
  bool verbose = false;
  #region Command Line Parsing
  switch ( args.Length )
  {
   case 0:
    return WriteError( string.Empty );
   case 1:
    filespec = args[0].Trim( '"' );
    break;
   case 2:
    filespec = args[0].Trim( '"' );
    if ( args[1].Substring( 0, 2 ).ToUpper( ) == "/V" )
    {
     verbose = true;
    }
    else
    {
     return WriteError( "Invalid command line switch: " + args[1] );
    }
    break;
   default:
    return WriteError( string.Empty );
  }
  if ( string.IsNullOrWhiteSpace( filespec ) || filespec == "/?" )
  {
   return WriteError( string.Empty );
  }
  if ( filespec.IndexOfAny( "/?".ToCharArray( 0, 2 ) ) != -1 )
  {
   return WriteError( "Invalid file specification: \"" + filespec + "\"" );
  }
  #endregion Command Line Parsing
  try
  {
   // Check if the directory exists
   try
   {
    dir = Path.GetDirectoryName( filespec );
    if ( string.IsNullOrWhiteSpace( dir ) )
    {
     dir = Path.GetFullPath( "." );
    }
    if ( !Directory.Exists( dir ) )
    {
     return WriteError( "Directory not found: \"" + dir + "\"" );
    }
    dir = dir.TrimEnd( trailingbackslash ) + "\\";
   }
   catch ( ArgumentException )
   {
    return WriteError( "Parent directory not found" );
   }
   // Extract the FILE specification (removing the path)
   string filenames = filespec.Substring( filespec.LastIndexOf( "\\" ) + 1 );
   // Enumerate the files
   string[] files = Directory.EnumerateFiles( dir, filenames ).ToArray<string>( );
   int count = 0;
   foreach ( string file in files )
   {
    if ( File.Exists( file ) )
    {
     string filename = Path.GetFileName( file );
     if ( filename.IndexOfAny( upcaseletters ) > -1 )
     {
      count++;
      string newfilename = dir + filename.ToLowerInvariant( );
      File.Move( file, newfilename );
     }
    }
   }
   if ( verbose )
   {
    Console.WriteLine( "{0} matching file{1} renamed", ( count == 0 ? "No" : count.ToString( ) ), ( count == 1 ? string.Empty : "s" ) );
   }
   return count;
  }
  catch ( Exception e )
  {
   return WriteError( e.Message );
  }
 }
 public static int WriteError( Exception e )
 {
  return WriteError( e == null ? null : e.Message );
 }
 public static int WriteError( string errorMessage )
 {
  if ( !string.IsNullOrWhiteSpace( errorMessage ) )
  {
   Console.Error.WriteLine( );
   Console.ForegroundColor = ConsoleColor.Red;
   Console.Error.Write( "ERROR: " );
   Console.ForegroundColor = ConsoleColor.White;
   Console.Error.WriteLine( errorMessage );
   Console.ResetColor( );
  }
  Console.Error.WriteLine( );
  Console.Error.WriteLine( "LoCase.exe, Version 1.02" );
  Console.Error.WriteLine( "Rename specified files to all lower case" );
  Console.Error.WriteLine( );
  Console.Error.Write( "Usage: " );
  Console.ForegroundColor = ConsoleColor.White;
  Console.Error.WriteLine( "LoCase.exe filespec [ /Verbose ]" );
  Console.ResetColor( );
  Console.Error.WriteLine( );
  Console.Error.Write( "Where: " );
  Console.ForegroundColor = ConsoleColor.White;
  Console.Error.Write( "filespec" );
  Console.ResetColor( );
  Console.Error.WriteLine( " is (are) the file(s) to be renamed (wildcards allowed)" );
  Console.ForegroundColor = ConsoleColor.White;
  Console.Error.Write( "   /V" );
  Console.ResetColor( );
  Console.Error.WriteLine( "erbose displays the number of files renamed" );
  Console.Error.WriteLine( );
  Console.Error.WriteLine( "Note:  Use doublequotes if filespec contains spaces." );
  Console.Error.WriteLine( "   Return code (\"ErrorLevel\") equals the number of renamed files." );
  Console.Error.Write( "   Switch may be abbreviated, e.g. " );
  Console.ForegroundColor = ConsoleColor.White;
  Console.Error.Write( "/V" );
  Console.ResetColor( );
  Console.Error.Write( " instead of " );
  Console.ForegroundColor = ConsoleColor.White;
  Console.Error.Write( "/V" );
  Console.ResetColor( );
  Console.Error.WriteLine( "erbose." );
  Console.Error.WriteLine( );
  Console.Error.WriteLine( "Written by Rob van der Woude" );
  return 0;
 }
}
}

希望本文所述对大家的C#程序设计有所帮助。