1 private static string GetSortedParas(Dictionary<string, string> dic) 2 { 3     dic = dic.OrderBy(key => key.Key).ToDictionary(keyItem => keyItem.Key, valueItem => valueItem.Value); 4     var sbPara = new StringBuilder(1024); 5     foreach (var para in dic.Where(para => !para.Value.IsNullOrWhiteSpace())) 6     { 7         sbPara.AppendFormat("{0}={1}&", para.Key, para.Value); 8     } 9     return sbPara.ToString().TrimEnd(‘&‘);10 }