Converting HTML entities to Unicode Characters in C#

Question

I found similar questions and answers for Python and Javascript, but not for C# or any other WinRT compatible language.

The reason I think I need it, is because I\'

Answer 1

Improved Zumey method (I can`t comment there). Max char size is in the entity: &exclamation; (11). Upper case in the entities are also possible, ex. À (Source from wiki)

public string EntityToUnicode(string html) {
        var replacements = new Dictionary();
        var regex = new Regex("(&[a-zA-Z]{2,11};)");
        foreach (Match match in regex.Matches(html)) {
            if (!replacements.ContainsKey(match.Value)) { 
                var unicode = HttpUtility.HtmlDecode(match.Value);
                if (unicode.Length == 1) {
                    replacements.Add(match.Value, string.Concat("&#", Convert.ToInt32(unicode[0]), ";"));
                }
            }
        }
        foreach (var replacement in replacements) {
            html = html.Replace(replacement.Key, replacement.Value);
        }
        return html;
    }