FormatDictionary

   public static string FormatDictionary(this string str, Dictionary<string, object> args)
        {
            var rex = new Regex("{.*?}");
            var groups = new List<string>();
            foreach (Match x in rex.Matches(str))
            {
                var strippedVal = x.Value.Trim('{', '}');
                if (!groups.Contains(strippedVal))
                    groups.Add(strippedVal);
            }
            var values = new List<object>();
            for (int i = 0; i < groups.Count; i++)
            {
                str = str.Replace("{" + groups[i] + "}", "{" + i + "}");
                values.Add(args.ContainsKey(groups[i]) ? args[groups[i]] : string.Empty);
            }
            return string.Format(str, values.ToArray());
            //return string.Format(str, args);
        }