System.IO.Path.Path.GetDirectoryName C# (CSharp) Méthode

		public static string GetDirectoryName (string path)
		{
			// LAMESPEC: For empty string MS docs say both
			// return null AND throw exception.  Seems .NET throws.
			if (path == String.Empty)
				throw new ArgumentException("Invalid path");

			if (path == null || GetPathRoot (path) == path)
				return null;

			if (path.Trim ().Length == 0)
				throw new ArgumentException ("Argument string consists of whitespace characters only.");

			if (path.IndexOfAny (System.IO.Path.InvalidPathChars) > -1)
				throw new ArgumentException ("Path contains invalid characters");

			int nLast = path.LastIndexOfAny (PathSeparatorChars);
			if (nLast == 0)
				nLast++;

			if (nLast > 0) {
				string ret = path.Substring (0, nLast);
				int l = ret.Length;

				if (l >= 2 && DirectorySeparatorChar == '\\' && ret [l - 1] == VolumeSeparatorChar)
					return ret + DirectorySeparatorChar;
				else {
					//
					// Important: do not use CanonicalizePath here, use
					// the custom CleanPath here, as this should not
					// return absolute paths
					//
					return CleanPath (ret);
				}
			}

			return String.Empty;
		}