mcs/class/corlib/System.IO/File.cs

   1 //
   2 // System.IO.File.cs
   3 //
   4 //
   5 // Authors:
   6 //   Miguel de Icaza (miguel@ximian.com)
   7 //   Jim Richardson  (develop@wtfo-guru.com)
   8 //   Dan Lewis       (dihlewis@yahoo.co.uk)
   9 //   Ville Palo      (vi64pa@kolumbus.fi)
  10 //
  11 // Copyright 2002 Ximian, Inc. http://www.ximian.com
  12 // Copyright (C) 2001 Moonlight Enterprises, All Rights Reserved
  13 // Copyright (C) 2004, 2006, 2010 Novell, Inc (http://www.novell.com)
  14 //
  15 // Permission is hereby granted, free of charge, to any person obtaining
  16 // a copy of this software and associated documentation files (the
  17 // "Software"), to deal in the Software without restriction, including
  18 // without limitation the rights to use, copy, modify, merge, publish,
  19 // distribute, sublicense, and/or sell copies of the Software, and to
  20 // permit persons to whom the Software is furnished to do so, subject to
  21 // the following conditions:
  22 //
  23 // The above copyright notice and this permission notice shall be
  24 // included in all copies or substantial portions of the Software.
  25 //
  26 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  27 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  28 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  29 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  30 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  31 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  32 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  33 //
  34
  35 using System;
  36 using System.Collections.Generic;
  37 using System.Diagnostics;
  38 using System.Security;
  39 using System.Text;
  40 using System.Runtime.InteropServices;
  41
  42 #if !NET_2_1
  43 using System.Security.AccessControl;
  44 #endif
  45
  46 namespace System.IO
  47 {
  48         [ComVisible (true)]
  49         public static class File
  50         {
  51                 public static void AppendAllText (string path, string contents)
  52                 {
  53                         using (TextWriter w = new StreamWriter (path, true)) {
  54                                 w.Write (contents);
  55                         }
  56                 }
  57
  58                 public static void AppendAllText (string path, string contents, Encoding encoding)
  59                 {
  60                         using (TextWriter w = new StreamWriter (path, true, encoding)) {
  61                                 w.Write (contents);
  62                         }
  63                 }
  64
  65                 public static StreamWriter AppendText (string path)
  66                 {
  67                         return new StreamWriter (path, true);
  68                 }
  69
  70                 public static void Copy (string sourceFileName, string destFileName)
  71                 {
  72                         Copy (sourceFileName, destFileName, false);
  73                 }
  74
  75                 public static void Copy (string sourceFileName, string destFileName, bool overwrite)
  76                 {
  77                         MonoIOError error;
  78
  79                         if (sourceFileName == null)
  80                                 throw new ArgumentNullException ("sourceFileName");
  81                         if (destFileName == null)
  82                                 throw new ArgumentNullException ("destFileName");
  83                         if (sourceFileName.Length == 0)
  84                                 throw new ArgumentException ("An empty file name is not valid.", "sourceFileName");
  85                         if (sourceFileName.Trim ().Length == 0 || sourceFileName.IndexOfAny (Path.InvalidPathChars) != -1)
  86                                 throw new ArgumentException ("The file name is not valid.");
  87                         if (destFileName.Length == 0)
  88                                 throw new ArgumentException ("An empty file name is not valid.", "destFileName");
  89                         if (destFileName.Trim ().Length == 0 || destFileName.IndexOfAny (Path.InvalidPathChars) != -1)
  90                                 throw new ArgumentException ("The file name is not valid.");
  91
  92                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
  93
  94                         if (!MonoIO.Exists (sourceFileName, out error))
  95                                 throw new FileNotFoundException (Locale.GetText ("{0} does not exist", sourceFileName), sourceFileName);
  96                         if ((GetAttributes (sourceFileName) & FileAttributes.Directory) == FileAttributes.Directory)
  97                                 throw new ArgumentException (Locale.GetText ("{0} is a directory", sourceFileName));
  98
  99                         if (MonoIO.Exists (destFileName, out error)) {
 100                                 if ((GetAttributes (destFileName) & FileAttributes.Directory) == FileAttributes.Directory)
 101                                         throw new ArgumentException (Locale.GetText ("{0} is a directory", destFileName));
 102                                 if (!overwrite)
 103                                         throw new IOException (Locale.GetText ("{0} already exists", destFileName));
 104                         }
 105
 106                         string DirName = Path.GetDirectoryName (destFileName);
 107                         if (DirName != String.Empty && !Directory.Exists (DirName))
 108                                 throw new DirectoryNotFoundException (Locale.GetText ("Destination directory not found: {0}",DirName));
 109
 110                         if (!MonoIO.CopyFile (sourceFileName, destFileName, overwrite, out error)) {
 111                                 string p = Locale.GetText ("{0}\" or \"{1}", sourceFileName, destFileName);
 112                                 throw MonoIO.GetException (p, error);
 113                         }
 114                 }
 115
 116                 public static FileStream Create (string path)
 117                 {
 118                         return Create (path, 8192);
 119                 }
 120
 121                 public static FileStream Create (string path, int bufferSize)
 122                 {
 123                         return new FileStream (path, FileMode.Create, FileAccess.ReadWrite,
 124                                 FileShare.None, bufferSize);
 125                 }
 126
 127 #if !NET_2_1
 128                 [MonoLimitation ("FileOptions are ignored")]
 129                 public static FileStream Create (string path, int bufferSize,
 130                                                  FileOptions options)
 131                 {
 132                         return Create (path, bufferSize, options, null);
 133                 }
 134
 135                 [MonoLimitation ("FileOptions and FileSecurity are ignored")]
 136                 public static FileStream Create (string path, int bufferSize,
 137                                                  FileOptions options,
 138                                                  FileSecurity fileSecurity)
 139                 {
 140                         return new FileStream (path, FileMode.Create, FileAccess.ReadWrite,
 141                                 FileShare.None, bufferSize, options);
 142                 }
 143 #endif
 144
 145                 public static StreamWriter CreateText (string path)
 146                 {
 147                         return new StreamWriter (path, false);
 148                 }
 149
 150                 public static void Delete (string path)
 151                 {
 152                         Path.Validate (path);
 153                         if (Directory.Exists (path))
 154                                 throw new UnauthorizedAccessException(Locale.GetText ("{0} is a directory", path));
 155
 156                         string DirName = Path.GetDirectoryName(path);
 157                         if (DirName != String.Empty && !Directory.Exists (DirName))
 158                                 throw new DirectoryNotFoundException (Locale.GetText ("Could not find a part of the path \"{0}\".", path));
 159
 160                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 161
 162                         MonoIOError error;
 163
 164                         if (!MonoIO.DeleteFile (path, out error)){
 165                                 if (error != MonoIOError.ERROR_FILE_NOT_FOUND)
 166                                         throw MonoIO.GetException (path, error);
 167                         }
 168                 }
 169
 170                 public static bool Exists (string path)
 171                 {
 172                         // For security reasons no exceptions are
 173                         // thrown, only false is returned if there is
 174                         // any problem with the path or permissions.
 175                         // Minimizes what information can be
 176                         // discovered by using this method.
 177                         if (String.IsNullOrWhiteSpace (path) || path.IndexOfAny(Path.InvalidPathChars) >= 0)
 178                                 return false;
 179
 180                         // on Moonlight this does not throw but returns false
 181                         if (!SecurityManager.CheckElevatedPermissions ())
 182                                 return false;
 183
 184                         MonoIOError error;
 185                         return MonoIO.ExistsFile (path, out error);
 186                 }
 187
 188 #if !NET_2_1
 189                 public static FileSecurity GetAccessControl (string path)
 190                 {
 191                         throw new NotImplementedException ();
 192                 }
 193
 194                 public static FileSecurity GetAccessControl (string path, AccessControlSections includeSections)
 195                 {
 196                         throw new NotImplementedException ();
 197                 }
 198 #endif
 199
 200                 public static FileAttributes GetAttributes (string path)
 201                 {
 202                         Path.Validate (path);
 203                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 204
 205                         MonoIOError error;
 206                         FileAttributes attrs;
 207
 208                         attrs = MonoIO.GetFileAttributes (path, out error);
 209                         if (error != MonoIOError.ERROR_SUCCESS)
 210                                 throw MonoIO.GetException (path, error);
 211                         return attrs;
 212                 }
 213
 214                 public static DateTime GetCreationTime (string path)
 215                 {
 216                         MonoIOStat stat;
 217                         MonoIOError error;
 218                         Path.Validate (path);
 219                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 220
 221                         if (!MonoIO.GetFileStat (path, out stat, out error)) {
 222                                 if (error == MonoIOError.ERROR_PATH_NOT_FOUND || error == MonoIOError.ERROR_FILE_NOT_FOUND)
 223                                         return DefaultLocalFileTime;
 224                                 else
 225                                         throw new IOException (path);
 226                         }
 227                         return DateTime.FromFileTime (stat.CreationTime);
 228                 }
 229
 230                 public static DateTime GetCreationTimeUtc (string path)
 231                 {
 232                         return GetCreationTime (path).ToUniversalTime ();
 233                 }
 234
 235                 public static DateTime GetLastAccessTime (string path)
 236                 {
 237                         MonoIOStat stat;
 238                         MonoIOError error;
 239                         Path.Validate (path);
 240                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 241
 242                         if (!MonoIO.GetFileStat (path, out stat, out error)) {
 243                                 if (error == MonoIOError.ERROR_PATH_NOT_FOUND || error == MonoIOError.ERROR_FILE_NOT_FOUND)
 244                                         return DefaultLocalFileTime;
 245                                 else
 246                                         throw new IOException (path);
 247                         }
 248                         return DateTime.FromFileTime (stat.LastAccessTime);
 249                 }
 250
 251                 public static DateTime GetLastAccessTimeUtc (string path)
 252                 {
 253                         return GetLastAccessTime (path).ToUniversalTime ();
 254                 }
 255
 256                 public static DateTime GetLastWriteTime (string path)
 257                 {
 258                         MonoIOStat stat;
 259                         MonoIOError error;
 260                         Path.Validate (path);
 261                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 262
 263                         if (!MonoIO.GetFileStat (path, out stat, out error)) {
 264                                 if (error == MonoIOError.ERROR_PATH_NOT_FOUND || error == MonoIOError.ERROR_FILE_NOT_FOUND)
 265                                         return DefaultLocalFileTime;
 266                                 else
 267                                         throw new IOException (path);
 268                         }
 269                         return DateTime.FromFileTime (stat.LastWriteTime);
 270                 }
 271
 272                 public static DateTime GetLastWriteTimeUtc (string path)
 273                 {
 274                         return GetLastWriteTime (path).ToUniversalTime ();
 275                 }
 276
 277                 public static void Move (string sourceFileName, string destFileName)
 278                 {
 279                         if (sourceFileName == null)
 280                                 throw new ArgumentNullException ("sourceFileName");
 281                         if (destFileName == null)
 282                                 throw new ArgumentNullException ("destFileName");
 283                         if (sourceFileName.Length == 0)
 284                                 throw new ArgumentException ("An empty file name is not valid.", "sourceFileName");
 285                         if (sourceFileName.Trim ().Length == 0 || sourceFileName.IndexOfAny (Path.InvalidPathChars) != -1)
 286                                 throw new ArgumentException ("The file name is not valid.");
 287                         if (destFileName.Length == 0)
 288                                 throw new ArgumentException ("An empty file name is not valid.", "destFileName");
 289                         if (destFileName.Trim ().Length == 0 || destFileName.IndexOfAny (Path.InvalidPathChars) != -1)
 290                                 throw new ArgumentException ("The file name is not valid.");
 291
 292                         SecurityManager.EnsureElevatedPermissions (); // this is a no-op outside moonlight
 293
 294                         MonoIOError error;
 295                         if (!MonoIO.Exists (sourceFileName, out error))
 296                                 throw new FileNotFoundException (Locale.GetText ("{0} does not exist", sourceFileName), sourceFileName);
 297
 298                         // Don't check for this error here to allow the runtime
 299                         // to check if sourceFileName and destFileName are equal.
 300                         // Comparing sourceFileName and destFileName is not enough.
 301                         //if (MonoIO.Exists (destFileName, out error))
 302                         //      throw new IOException (Locale.GetText ("{0} already exists", destFileName));
 303
 304                         string DirName;
 305                         DirName = Path.GetDirectoryName (destFileName);
 306                         if (DirName != String.Empty && !Directory.Exists (DirName))
 307                                 throw new DirectoryNotFoundException (Locale.GetText ("Could not find a part of the path."));
 308
 309                         if (!MonoIO.MoveFile (sourceFileName, destFileName, out error)) {
 310                                 if (error == MonoIOError.ERROR_ALREADY_EXISTS)
 311                                         throw MonoIO.GetException (error);
 312                                 else if (error == MonoIOError.ERROR_SHARING_VIOLATION)
 313                                         throw MonoIO.GetException (sourceFileName, error);
 314
 315                                 throw MonoIO.GetException (error);
 316                         }
 317                 }
 318
 319                 public static FileStream Open (string path, FileMode mode)
 320                 {
 321                         return new FileStream (path, mode, mode == FileMode.Append ? FileAccess.Write : FileAccess.ReadWrite, FileShare.None);
 322                 }
 323
 324                 public static FileStream Open (string path, FileMode mode, FileAccess access)
 325                 {
 326                         return new FileStream (path, mode, access, FileShare.None);
 327                 }
 328
 329                 public static FileStream Open (string path, FileMode mode, FileAccess access,
 330                                                FileShare share)
 331                 {
 332                         return new FileStream (path, mode, access, share);
 333                 }
 334
 335                 public static FileStream OpenRead (string path)
 336                 {
 337                         return new FileStream (path, FileMode.Open, FileAccess.Read, FileShare.Read);
 338                 }
 339
 340                 public static StreamReader OpenText (string path)
 341                 {
 342                         return new StreamReader (path);
 343                 }
 344
 345                 public static FileStream OpenWrite (string path)
 346                 {
 347                         return new FileStream(path, FileMode.OpenOrCreate, FileAccess.Write, FileShare.None);
 348                 }
 349
 350                 public static void Replace (string sourceFileName,
 351                                             string destinationFileName,
 352                                             string destinationBackupFileName)
 353                 {
 354                         Replace (sourceFileName, destinationFileName, destinationBackupFileName, false);
 355                 }
 356
 357                 public static void Replace (string sourceFileName,
 358                                             string destinationFileName,
 359                                             string destinationBackupFileName,
 360                                             bool ignoreMetadataErrors)
 361                 {
 362                         MonoIOError error;
 363
 364                         if (sourceFileName == null)
 365                                 throw new ArgumentNullException ("sourceFileName");
 366                         if (destinationFileName == null)
 367                                 throw new ArgumentNullException ("destinationFileName");
 368                         if (sourceFileName.Trim ().Length == 0 || sourceFileName.IndexOfAny (Path.InvalidPathChars) != -1)
 369                                 throw new ArgumentException ("sourceFileName");
 370                         if (destinationFileName.Trim ().Length == 0 || destinationFileName.IndexOfAny (Path.InvalidPathChars) != -1)
 371                                 throw new ArgumentException ("destinationFileName");
 372
 373                         string fullSource = Path.GetFullPath (sourceFileName);
 374                         string fullDest = Path.GetFullPath (destinationFileName);
 375                         if (MonoIO.ExistsDirectory (fullSource, out error))
 376                                 throw new IOException (Locale.GetText ("{0} is a directory", sourceFileName));
 377                         if (MonoIO.ExistsDirectory (fullDest, out error))
 378                                 throw new IOException (Locale.GetText ("{0} is a directory", destinationFileName));
 379
 380                         if (!Exists (fullSource))
 381                                 throw new FileNotFoundException (Locale.GetText ("{0} does not exist", sourceFileName),
 382                                                                  sourceFileName);
 383                         if (!Exists (fullDest))
 384                                 throw new FileNotFoundException (Locale.GetText ("{0} does not exist", destinationFileName),
 385                                                                  destinationFileName);
 386                         if (fullSource == fullDest)
 387                                 throw new IOException (Locale.GetText ("Source and destination arguments are the same file."));
 388
 389                         string fullBackup = null;
 390                         if (destinationBackupFileName != null) {
 391                                 if (destinationBackupFileName.Trim ().Length == 0 ||
 392                                     destinationBackupFileName.IndexOfAny (Path.InvalidPathChars) != -1)
 393                                         throw new ArgumentException ("destinationBackupFileName");
 394
 395                                 fullBackup = Path.GetFullPath (destinationBackupFileName);
 396                                 if (MonoIO.ExistsDirectory (fullBackup, out error))
 397                                         throw new IOException (Locale.GetText ("{0} is a directory", destinationBackupFileName));
 398                                 if (fullSource == fullBackup)
 399                                         throw new IOException (Locale.GetText ("Source and backup arguments are the same file."));
 400                                 if (fullDest == fullBackup)
 401                                         throw new IOException (Locale.GetText (
 402                                                                "Destination and backup arguments are the same file."));
 403                         }
 404
 405                         if (!MonoIO.ReplaceFile (fullSource, fullDest, fullBackup,
 406                                                  ignoreMetadataErrors, out error)) {
 407                                 throw MonoIO.GetException (error);
 408                         }
 409                 }
 410
 411 #if !NET_2_1
 412                 public static void SetAccessControl (string path,
 413                                                      FileSecurity fileSecurity)
 414                 {
 415                         throw new NotImplementedException ();
 416                 }
 417 #endif
 418
 419                 public static void SetAttributes (string path,
 420                                                   FileAttributes fileAttributes)
 421                 {
 422                         MonoIOError error;
 423                         Path.Validate (path);
 424
 425                         if (!MonoIO.SetFileAttributes (path, fileAttributes, out error))
 426                                 throw MonoIO.GetException (path, error);
 427                 }
 428
 429                 public static void SetCreationTime (string path, DateTime creationTime)
 430                 {
 431                         MonoIOError error;
 432                         Path.Validate (path);
 433                         if (!MonoIO.Exists (path, out error))
 434                                 throw MonoIO.GetException (path, error);
 435                         if (!MonoIO.SetCreationTime (path, creationTime, out error))
 436                                 throw MonoIO.GetException (path, error);
 437                 }
 438
 439                 public static void SetCreationTimeUtc (string path, DateTime creationTimeUtc)
 440                 {
 441                         SetCreationTime (path, creationTimeUtc.ToLocalTime ());
 442                 }
 443
 444                 public static void SetLastAccessTime (string path, DateTime lastAccessTime)
 445                 {
 446                         MonoIOError error;
 447                         Path.Validate (path);
 448                         if (!MonoIO.Exists (path, out error))
 449                                 throw MonoIO.GetException (path, error);
 450                         if (!MonoIO.SetLastAccessTime (path, lastAccessTime, out error))
 451                                 throw MonoIO.GetException (path, error);
 452                 }
 453
 454                 public static void SetLastAccessTimeUtc (string path, DateTime lastAccessTimeUtc)
 455                 {
 456                         SetLastAccessTime (path, lastAccessTimeUtc.ToLocalTime ());
 457                 }
 458
 459                 public static void SetLastWriteTime (string path,
 460                                                      DateTime lastWriteTime)
 461                 {
 462                         MonoIOError error;
 463                         Path.Validate (path);
 464                         if (!MonoIO.Exists (path, out error))
 465                                 throw MonoIO.GetException (path, error);
 466                         if (!MonoIO.SetLastWriteTime (path, lastWriteTime, out error))
 467                                 throw MonoIO.GetException (path, error);
 468                 }
 469
 470                 public static void SetLastWriteTimeUtc (string path,
 471                                                      DateTime lastWriteTimeUtc)
 472                 {
 473                         SetLastWriteTime (path, lastWriteTimeUtc.ToLocalTime ());
 474                 }
 475
 476                 //
 477                 // The documentation for this method is most likely wrong, it
 478                 // talks about doing a "binary read", but the remarks say
 479                 // that this "detects the encoding".
 480                 //
 481                 // This can not detect and do anything useful with the encoding
 482                 // since the result is a byte [] not a char [].
 483                 //
 484                 public static byte [] ReadAllBytes (string path)
 485                 {
 486                         using (FileStream s = OpenRead (path)) {
 487                                 long size = s.Length;
 488                                 // limited to 2GB according to http://msdn.microsoft.com/en-us/library/system.io.file.readallbytes.aspx
 489                                 if (size > Int32.MaxValue)
 490                                         throw new IOException ("Reading more than 2GB with this call is not supported");
 491
 492                                 int pos = 0;
 493                                 int count = (int) size;
 494                                 byte [] result = new byte [size];
 495                                 while (count > 0) {
 496                                         int n = s.Read (result, pos, count);
 497                                         if (n == 0)
 498                                                 throw new IOException ("Unexpected end of stream");
 499                                         pos += n;
 500                                         count -= n;
 501                                 }
 502                                 return result;
 503                         }
 504                 }
 505
 506                 public static string [] ReadAllLines (string path)
 507                 {
 508                         using (StreamReader reader = File.OpenText (path)) {
 509                                 return ReadAllLines (reader);
 510                         }
 511                 }
 512
 513                 public static string [] ReadAllLines (string path, Encoding encoding)
 514                 {
 515                         using (StreamReader reader = new StreamReader (path, encoding)) {
 516                                 return ReadAllLines (reader);
 517                         }
 518                 }
 519
 520                 static string [] ReadAllLines (StreamReader reader)
 521                 {
 522                         List<string> list = new List<string> ();
 523                         while (!reader.EndOfStream)
 524                                 list.Add (reader.ReadLine ());
 525                         return list.ToArray ();
 526                 }
 527
 528                 public static string ReadAllText (string path)
 529                 {
 530                         using (StreamReader sr = new StreamReader (path)) {
 531                                 return sr.ReadToEnd ();
 532                         }
 533                 }
 534
 535                 public static string ReadAllText (string path, Encoding encoding)
 536                 {
 537                         using (StreamReader sr = new StreamReader (path, encoding)) {
 538                                 return sr.ReadToEnd ();
 539                         }
 540                 }
 541
 542                 public static void WriteAllBytes (string path, byte [] bytes)
 543                 {
 544                         using (Stream stream = File.Create (path)) {
 545                                 stream.Write (bytes, 0, bytes.Length);
 546                         }
 547                 }
 548
 549                 public static void WriteAllLines (string path, string [] contents)
 550                 {
 551                         using (StreamWriter writer = new StreamWriter (path)) {
 552                                 WriteAllLines (writer, contents);
 553                         }
 554                 }
 555
 556                 public static void WriteAllLines (string path, string [] contents, Encoding encoding)
 557                 {
 558                         using (StreamWriter writer = new StreamWriter (path, false, encoding)) {
 559                                 WriteAllLines (writer, contents);
 560                         }
 561                 }
 562
 563                 static void WriteAllLines (StreamWriter writer, string [] contents)
 564                 {
 565                         foreach (string line in contents)
 566                                 writer.WriteLine (line);
 567                 }
 568
 569                 public static void WriteAllText (string path, string contents)
 570                 {
 571                         WriteAllText (path, contents, Encoding.UTF8Unmarked);
 572                 }
 573
 574                 public static void WriteAllText (string path, string contents, Encoding encoding)
 575                 {
 576                         using (StreamWriter sw = new StreamWriter (path, false, encoding)) {
 577                                 sw.Write (contents);
 578                         }
 579                 }
 580
 581                 static DateTime? defaultLocalFileTime;
 582                 static DateTime DefaultLocalFileTime {
 583                         get {
 584                                 if (defaultLocalFileTime == null)
 585                                         defaultLocalFileTime = new DateTime (1601, 1, 1).ToLocalTime ();
 586
 587                                 return defaultLocalFileTime.Value;
 588                         }
 589                 }
 590
 591
 592                 [MonoLimitation ("File encryption isn't supported (even on NTFS).")]
 593                 public static void Encrypt (string path)
 594                 {
 595                         // MS.NET support this only on NTFS file systems, i.e. it's a file-system (not a framework) feature.
 596                         // otherwise it throws a NotSupportedException (or a PlatformNotSupportedException on older OS).
 597                         // we throw the same (instead of a NotImplementedException) because most code should already be
 598                         // handling this exception to work properly.
 599                         throw new NotSupportedException (Locale.GetText ("File encryption isn't supported on any file system."));
 600                 }
 601
 602                 [MonoLimitation ("File encryption isn't supported (even on NTFS).")]
 603                 public static void Decrypt (string path)
 604                 {
 605                         // MS.NET support this only on NTFS file systems, i.e. it's a file-system (not a framework) feature.
 606                         // otherwise it throws a NotSupportedException (or a PlatformNotSupportedException on older OS).
 607                         // we throw the same (instead of a NotImplementedException) because most code should already be
 608                         // handling this exception to work properly.
 609                         throw new NotSupportedException (Locale.GetText ("File encryption isn't supported on any file system."));
 610                 }
 611
 612 #if MOONLIGHT || NET_4_0
 613                 public static IEnumerable<string> ReadLines (string path)
 614                 {
 615                         using (StreamReader reader = File.OpenText (path)) {
 616                                 return ReadLines (reader);
 617                         }
 618                 }
 619
 620                 public static IEnumerable<string> ReadLines (string path, Encoding encoding)
 621                 {
 622                         using (StreamReader reader = new StreamReader (path, encoding)) {
 623                                 return ReadLines (reader);
 624                         }
 625                 }
 626
 627                 // refactored in order to avoid compiler-generated names for Moonlight tools
 628                 static IEnumerable<string> ReadLines (StreamReader reader)
 629                 {
 630                         string s;
 631                         while ((s = reader.ReadLine ()) != null)
 632                                 yield return s;
 633                 }
 634
 635                 public static void AppendAllLines (string path, IEnumerable<string> contents)
 636                 {
 637                         Path.Validate (path);
 638
 639                         if (contents == null)
 640                                 return;
 641
 642                         using (TextWriter w = new StreamWriter (path, true)) {
 643                                 foreach (var line in contents)
 644                                         w.Write (line);
 645                         }
 646                 }
 647
 648                 public static void AppendAllLines (string path, IEnumerable<string> contents, Encoding encoding)
 649                 {
 650                         Path.Validate (path);
 651
 652                         if (contents == null)
 653                                 return;
 654
 655                         using (TextWriter w = new StreamWriter (path, true, encoding)) {
 656                                 foreach (var line in contents)
 657                                         w.Write (line);
 658                         }
 659                 }
 660
 661                 public static void WriteAllLines (string path, IEnumerable<string> contents)
 662                 {
 663                         Path.Validate (path);
 664
 665                         if (contents == null)
 666                                 return;
 667
 668                         using (TextWriter w = new StreamWriter (path, false)) {
 669                                 foreach (var line in contents)
 670                                         w.Write (line);
 671                         }
 672                 }
 673
 674                 public static void WriteAllLines (string path, IEnumerable<string> contents, Encoding encoding)
 675                 {
 676                         Path.Validate (path);
 677
 678                         if (contents == null)
 679                                 return;
 680
 681                         using (TextWriter w = new StreamWriter (path, false, encoding)) {
 682                                 foreach (var line in contents)
 683                                         w.Write (line);
 684                         }
 685                 }
 686 #endif
 687         }
 688 }