HtmlEntities

#region GetOnlyTextFromHtmlCode + RemoveHtmlChars + RemoveTagFromHtmlCode
        /// <summary>
        /// http://www.codeproject.com/script/Content/ViewAssociatedFile.aspx?rzp=%2FKB%2Fedit%2FZetaHtmlEditControl%2F%2FZetaHtmlEditControl-Source.zip&zep=Control%2FHtmlEditControl.cs&obid=43954&obtid=2&ovid=13
        /// </summary>
        /// <param name="htmlCode"></param>
        /// <returns></returns>
        private static string getOnlyTextFromHtmlCode(string htmlCode)
        {
            //<br>
            htmlCode = htmlCode.Replace("\r\n", @" ");
            htmlCode = htmlCode.Replace("\r", @" ");
            htmlCode = htmlCode.Replace("\n", @" ");

            htmlCode = htmlCode.Replace(@"</p>", Environment.NewLine + Environment.NewLine);
            htmlCode = htmlCode.Replace(@"</P>", Environment.NewLine + Environment.NewLine);

            //html comment
            htmlCode = Regex.Replace(
                htmlCode,
                @"<!--.*?-->",
                string.Empty,
                RegexOptions.Singleline | RegexOptions.IgnoreCase);

            //<p>
            htmlCode = Regex.Replace(htmlCode,
                @"<br[^>]*>",
                Environment.NewLine,
                RegexOptions.Singleline | RegexOptions.IgnoreCase);

            //tags
            htmlCode = removeTagFromHtmlCode(@"style", htmlCode);
            htmlCode = removeTagFromHtmlCode(@"script", htmlCode);

            //html
            htmlCode = Regex.Replace(
                htmlCode,
                "<(.|\n)+?>",
                string.Empty,
                RegexOptions.Singleline | RegexOptions.IgnoreCase);

            //umlaute
            htmlCode = unescapeHtmlEntities(htmlCode);

            //whitespaces
            htmlCode = Regex.Replace(
                htmlCode,
                @" +",
                @" ",
                RegexOptions.Singleline | RegexOptions.IgnoreCase);

            return htmlCode;
        }
        /// <summary>
        /// http://dev.w3.org/html5/html-author/charref
        /// </summary>
        /// <param name="htmlCode"></param>
        /// <returns></returns>
        private static string unescapeHtmlEntities(string htmlCode)
        {

　　　　　　htmlCode = htmlCode.Replace(@" ", @" ");

　　　　　　htmlCode = htmlCode.Replace(@"Ä", @"ä");
　　　　　　htmlCode = htmlCode.Replace(@"&absp;", @"");
　　　　　　htmlCode = htmlCode.Replace(@"&obsp;", @"");
　　　　　　htmlCode = htmlCode.Replace(@"&Obsp;", @"");
　　　　　　htmlCode = htmlCode.Replace(@"&ubsp;", @"");
　　　　　　htmlCode = htmlCode.Replace(@"&Ubsp;", @"");
　　　　　　htmlCode = htmlCode.Replace(@"ß", @"ß");

　　　　　　htmlCode = htmlCode.Replace(@"£", @"£");
　　　　　　htmlCode = htmlCode.Replace(@"§", @"§");
　　　　　　htmlCode = htmlCode.Replace(@"©", @"©");
　　　　　　htmlCode = htmlCode.Replace(@"®", @"®");
　　　　　　htmlCode = htmlCode.Replace(@"µ", @"µ");
　　　　　　htmlCode = htmlCode.Replace(@"¶", @"¶");
　　　　　　htmlCode = htmlCode.Replace(@"Ø", @"Ø");
　　　　　　htmlCode = htmlCode.Replace(@"ø", @"Ø");
　　　　　　htmlCode = htmlCode.Replace(@"÷", @"÷");
　　　　　　htmlCode = htmlCode.Replace(@"×", @"×");

            return htmlCode;
        }

        private static string removeTagFromHtmlCode(
            string tag,
            string htmlCode)
        {
            return Regex.Replace(
                htmlCode,
                string.Format(@"<{0}.*?</{1}>", tag, tag),
                string.Empty,
                RegexOptions.Singleline | RegexOptions.IgnoreCase);
        }
        #endregion