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public static Encoding GetFileEncoding( string filePath) { Encoding encoding = null; FileStream fStream = File.Open(filePath, FileMode.Open); if (fStream.CanSeek) { byte[] data = new byte[4]; fStream.Read(data, 0, 4); int markerLength = 0; switch (data[0]) { case 0xef: // UTF8 markerLength = 3; if (data.Length < 3) break; if (data[1] == 0xbb && data[2] == 0xbf) encoding = Encoding.UTF8; break; case 0xfe: // UTF 16 BE markerLength = 2; if (data[1] == 0xff) encoding = Encoding.BigEndianUnicode; break; case 0xff: // UTF 16 LE markerLength = 2; if (data[1] == 0xfe) encoding = Encoding.Unicode; break; default: encoding = Encoding.ASCII; break; } } fStream.Dispose(); fStream.Close(); fStream = null; return encoding; }