public static string FormatWith(this string format, IFormatProvider provider, object source)
        {
            if (format == null)

                throw new ArgumentNullException("format");

            Regex r = new Regex(@"\{\{|\{([\w\.\[\]]+)((?:[,:][^}]+)?\})",
 RegexOptions.Compiled | RegexOptions.CultureInvariant | RegexOptions.IgnoreCase);

            List<object> values = new List<object>();
            string rewrittenFormat = r.Replace(format, delegate(Match m)
            {
                string propertyName = m.Groups[1].Value;

                if (propertyName.Length == 0)
                    return m.Value;

                values.Add(propertyName == "0" ? source : DataBinder.Eval(source, propertyName));

                string len = m.Groups[2].Value.Replace(",", "").Replace("}", "").Replace(" ", "").Replace(":","");
                if (!String.IsNullOrEmpty(len))
                {
                    int leng;
                    if (Int32.TryParse(len, out leng))
                    {
                        string value = values[values.Count - 1].ToString();
                        value = value.Substring(0, leng);
                        values[values.Count - 1] = value;
                    }
                }
                return "{" + (values.Count - 1) +"}";
            });
            return string.Format(provider, rewrittenFormat, values.ToArray());
        }