replace .cs

gistfile1.txt

public class HtmlHelper
    {
        string _attrib = string.Empty;

        public string AddAttribute(string source, string tagName, string attrib)
        {
            _attrib = attrib;

            string term = "<" + tagName + " [^>]+>";

            Regex r = new Regex(term, RegexOptions.IgnoreCase);

            MatchEvaluator myEvaluator = new MatchEvaluator(this.ProcessMatch);

            return r.Replace(source, myEvaluator);

        }



        private string ProcessMatch(Match m)
        {
            string tag = m.Value;
            if (tag.IndexOf(_attrib) == -1)
            {
                tag = tag.Replace(">", " " + _attrib + ">");
            }

            return tag;
        }


        public string ReplaceTag(string input, string oldTag, string newTag)
        {
            string pattern = @"(</?)"+oldTag+"([^>]*>)";
            string replacement = "$1"+ newTag + "$2";
            return   Regex.Replace(input, pattern, replacement);

        }
    }

HtmlHelper helper = new HtmlHelper();
htmlText = helper.ReplaceTag(htmlText, "inline-image", "img");
htmlText = helper.AddAttribute(htmlText, "img", "src="_blank"");