Смена кодировки utf-8 на unicode у русских букв

            string utf8String = @"\u0410\u0410";
            Encoding unicode = Encoding.Unicode;
            Encoding utf8 = Encoding.UTF8;
 
            byte[] utf8bytes = utf8.GetBytes(utf8String);
 
            byte[] unicodeBytes = Encoding.Convert(utf8, unicode, utf8bytes);
 
            char[] unicodeChars = new char[unicode.GetCharCount(unicodeBytes, 0, unicodeBytes.Length)];
            unicode.GetChars(unicodeBytes, 0, unicodeBytes.Length, unicodeChars, 0);
            textBox1.Text = new string(unicodeChars);

string utf8String = @"\u0410\u0410";
var query = from encodedCharacter in Regex.Split(utf8String, @"\u")
            select Convert.ToUInt16(encodedCharacter, 16) into unicodeCodePoint
            select (char)unicodeCodePoint;
 
string unicodeString = new string(query.ToArray());

string s = "\u0410\u0410";
s = Regex.Replace(s, @"\\u([a-fA-F\d]{4})", m => ((char)Convert.ToInt32(m.Groups[0].Value, 16)).ToString());

string utf8String = @"\u0410\u0410";
var query = from hex in utf8String.Split(new[]{@"\u"}, StringSplitOptions.RemoveEmptyEntries)
            select (char)Convert.ToUInt16(hex, 16);
string unicodeString = new string(query.ToArray());