1     public class Words 2     { 3         public static Dictionary<string, int> CountWords(string text) 4         { 5             Dictionary<string, int> frequencies;//创建从单词到频率的新映射 6             frequencies = new Dictionary<string, int>(); 7             string[] words = Regex.Split(text, @"\W+");//将文本分解成单词 8             //添加或跟新映射 9             foreach (var word in words)10             {11                 if (frequencies.ContainsKey(word))12                 {13                     frequencies[word]++;14                 }15                 else16                 {17                     frequencies[word] = 1;18                 }19             }20             return frequencies;21         }22     }

 1   static void Main(string[] args) 2   { 3       string text = "President Xi Jinping has asked the armed forces to clear up the bad influence left by the graft case of Xu Caihou, a former senior commander."; 4       Dictionary<string, int> frequencies = Words.CountWords(text); 5       foreach (KeyValuePair<string,int> entry in frequencies) 6       { 7           string word = entry.Key; 8           int frequency = entry.Value; 9           Console.WriteLine("{0}:{1}", word, frequency);10       }11       Console.ReadKey();12   }