件)的英文

用linq就可以. private string StatisticsLetters(string text) { StringBuilder sb = new StringBuilder(); string s = text; var statistics = from c in s group c by c into g select new { g.Key,count = g.Count() }; var mostFrequestFirst = from entry in statistics orderby entry.count descending select entry; foreach (var entry in mostFrequestFirst) { sb.AppendFormat("{0}:{1}{2}",entry.Key,entry.count,System.Environment.NewLine); } return sb.ToString(); }