I know this question is very old, but only for completeness: this guy wrote a class that translates RTF into plain text, like the OP request. Here is the source
This is his code:
/// <summary> /// Rich Text Stripper /// </summary> /// <remarks> /// Translated from Python located at: /// http://stackoverflow.com/a/188877/448 /// </remarks> public static class RichTextStripper { private class StackEntry { public int NumberOfCharactersToSkip { get; set; } public bool Ignorable { get; set; } public StackEntry(int numberOfCharactersToSkip, bool ignorable) { NumberOfCharactersToSkip = numberOfCharactersToSkip; Ignorable = ignorable; } } private static readonly Regex _rtfRegex = new Regex(@"\\([az]{1,32})(-?\d{1,10})?[ ]?|\\'([0-9a-f]{2})|\\([^az])|([{}])|[\r\n]+|(.)", RegexOptions.Singleline | RegexOptions.IgnoreCase); private static readonly List<string> destinations = new List<string> { "aftncn","aftnsep","aftnsepc","annotation","atnauthor","atndate","atnicn","atnid", "atnparent","atnref","atntime","atrfend","atrfstart","author","background", "bkmkend","bkmkstart","blipuid","buptim","category","colorschememapping", "colortbl","comment","company","creatim","datafield","datastore","defchp","defpap", "do","doccomm","docvar","dptxbxtext","ebcend","ebcstart","factoidname","falt", "fchars","ffdeftext","ffentrymcr","ffexitmcr","ffformat","ffhelptext","ffl", "ffname","ffstattext","field","file","filetbl","fldinst","fldrslt","fldtype", "fname","fontemb","fontfile","fonttbl","footer","footerf","footerl","footerr", "footnote","formfield","ftncn","ftnsep","ftnsepc","g","generator","gridtbl", "header","headerf","headerl","headerr","hl","hlfr","hlinkbase","hlloc","hlsrc", "hsv","htmltag","info","keycode","keywords","latentstyles","lchars","levelnumbers", "leveltext","lfolevel","linkval","list","listlevel","listname","listoverride", "listoverridetable","listpicture","liststylename","listtable","listtext", "lsdlockedexcept","macc","maccPr","mailmerge","maln","malnScr","manager","margPr", "mbar","mbarPr","mbaseJc","mbegChr","mborderBox","mborderBoxPr","mbox","mboxPr", "mchr","mcount","mctrlPr","md","mdeg","mdegHide","mden","mdiff","mdPr","me", "mendChr","meqArr","meqArrPr","mf","mfName","mfPr","mfunc","mfuncPr","mgroupChr", "mgroupChrPr","mgrow","mhideBot","mhideLeft","mhideRight","mhideTop","mhtmltag", "mlim","mlimloc","mlimlow","mlimlowPr","mlimupp","mlimuppPr","mm","mmaddfieldname", "mmath","mmathPict","mmathPr","mmaxdist","mmc","mmcJc","mmconnectstr", "mmconnectstrdata","mmcPr","mmcs","mmdatasource","mmheadersource","mmmailsubject", "mmodso","mmodsofilter","mmodsofldmpdata","mmodsomappedname","mmodsoname", "mmodsorecipdata","mmodsosort","mmodsosrc","mmodsotable","mmodsoudl", "mmodsoudldata","mmodsouniquetag","mmPr","mmquery","mmr","mnary","mnaryPr", "mnoBreak","mnum","mobjDist","moMath","moMathPara","moMathParaPr","mopEmu", "mphant","mphantPr","mplcHide","mpos","mr","mrad","mradPr","mrPr","msepChr", "mshow","mshp","msPre","msPrePr","msSub","msSubPr","msSubSup","msSubSupPr","msSup", "msSupPr","mstrikeBLTR","mstrikeH","mstrikeTLBR","mstrikeV","msub","msubHide", "msup","msupHide","mtransp","mtype","mvertJc","mvfmf","mvfml","mvtof","mvtol", "mzeroAsc","mzeroDesc","mzeroWid","nesttableprops","nextfile","nonesttables", "objalias","objclass","objdata","object","objname","objsect","objtime","oldcprops", "oldpprops","oldsprops","oldtprops","oleclsid","operator","panose","password", "passwordhash","pgp","pgptbl","picprop","pict","pn","pnseclvl","pntext","pntxta", "pntxtb","printim","private","propname","protend","protstart","protusertbl","pxe", "result","revtbl","revtim","rsidtbl","rxe","shp","shpgrp","shpinst", "shppict","shprslt","shptxt","sn","sp","staticval","stylesheet","subject","sv", "svb","tc","template","themedata","title","txe","ud","upr","userprops", "wgrffmtfilter","windowcaption","writereservation","writereservhash","xe","xform", "xmlattrname","xmlattrvalue","xmlclose","xmlname","xmlnstbl", "xmlopen" }; private static readonly Dictionary<string, string> specialCharacters = new Dictionary<string, string> { { "par", "\n" }, { "sect", "\n\n" }, { "page", "\n\n" }, { "line", "\n" }, { "tab", "\t" }, { "emdash", "\u2014" }, { "endash", "\u2013" }, { "emspace", "\u2003" }, { "enspace", "\u2002" }, { "qmspace", "\u2005" }, { "bullet", "\u2022" }, { "lquote", "\u2018" }, { "rquote", "\u2019" }, { "ldblquote", "\u201C" }, { "rdblquote", "\u201D" }, }; /// <summary> /// Strip RTF Tags from RTF Text /// </summary> /// <param name="inputRtf">RTF formatted text</param> /// <returns>Plain text from RTF</returns> public static string StripRichTextFormat(string inputRtf) { if (inputRtf == null) { return null; } string returnString; var stack = new Stack<StackEntry>(); bool ignorable = false; // Whether this group (and all inside it) are "ignorable". int ucskip = 1; // Number of ASCII characters to skip after a unicode character. int curskip = 0; // Number of ASCII characters left to skip var outList = new List<string>(); // Output buffer. MatchCollection matches = _rtfRegex.Matches(inputRtf); if (matches.Count > 0) { foreach (Match match in matches) { string word = match.Groups[1].Value; string arg = match.Groups[2].Value; string hex = match.Groups[3].Value; string character = match.Groups[4].Value; string brace = match.Groups[5].Value; string tchar = match.Groups[6].Value; if (!String.IsNullOrEmpty(brace)) { curskip = 0; if (brace == "{") { // Push state stack.Push(new StackEntry(ucskip, ignorable)); } else if (brace == "}") { // Pop state StackEntry entry = stack.Pop(); ucskip = entry.NumberOfCharactersToSkip; ignorable = entry.Ignorable; } } else if (!String.IsNullOrEmpty(character)) // \x (not a letter) { curskip = 0; if (character == "~") { if (!ignorable) { outList.Add("\xA0"); } } else if ("{}\\".Contains(character)) { if (!ignorable) { outList.Add(character); } } else if (character == "*") { ignorable = true; } } else if (!String.IsNullOrEmpty(word)) // \foo { curskip = 0; if (destinations.Contains(word)) { ignorable = true; } else if (ignorable) { } else if (specialCharacters.ContainsKey(word)) { outList.Add(specialCharacters[word]); } else if (word == "uc") { ucskip = Int32.Parse(arg); } else if (word == "u") { int c = Int32.Parse(arg); if (c < 0) { c += 0x10000; } outList.Add(Char.ConvertFromUtf32(c)); curskip = ucskip; } } else if (!String.IsNullOrEmpty(hex)) // \'xx { if (curskip > 0) { curskip -= 1; } else if (!ignorable) { int c = Int32.Parse(hex, System.Globalization.NumberStyles.HexNumber); outList.Add(Char.ConvertFromUtf32(c)); } } else if (!String.IsNullOrEmpty(tchar)) { if (curskip > 0) { curskip -= 1; } else if (!ignorable) { outList.Add(tchar); } } } } else { // Didn't match the regex returnString = inputRtf; } returnString = String.Join(String.Empty, outList.ToArray()); return returnString; } }