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

            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,
                "<(.|
)+?>",
                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(@"&nbsp;", @" ");

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

      htmlCode = htmlCode.Replace(@"&pound;", @"£");
      htmlCode = htmlCode.Replace(@"&sect;", @"§");
      htmlCode = htmlCode.Replace(@"&copy;", @"©");
      htmlCode = htmlCode.Replace(@"&reg;", @"®");
      htmlCode = htmlCode.Replace(@"&micro;", @"µ");
      htmlCode = htmlCode.Replace(@"&para;", @"¶");
      htmlCode = htmlCode.Replace(@"&Oslash;", @"Ø");
      htmlCode = htmlCode.Replace(@"&oslash;", @"Ø");
      htmlCode = htmlCode.Replace(@"&divide;", @"÷");
      htmlCode = htmlCode.Replace(@"&times;", @"×");

            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

  

原文地址:https://www.cnblogs.com/geovindu/p/4310328.html