性能全部损耗在排序上,由于hashtable不能排序,所以只能借助其他来排序,  不过还好  一本60000字的书10几秒就能统计完.

using System.IO;

using System.Collections;//use hashtable

using System.Text.RegularExpressions;

namespace WindowsApplication1

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void cmdStart_Click(object sender, EventArgs e)

        {

            string Pattern = @"\,|\.|\ |\n|\r|\?|\;|\:|\!|\(|\)|\042|\“|\”|\-|[\u4e00-\u9fa5]|[0-9]";   //匹配正值表达式 逗号，点号，空格，换行符，回车符，问号，,分号，，冒号，感叹号，，左括号，又括号，双引号，左双引号，右双引号，中文字符,数字

            string textstring = "";

            int j;

            Hashtable ht = new Hashtable();      //创建一个Hashtable实例

            //Hashtable ht = new Hashtable();      //创建一个Hashtable实例

            Regex regex = new Regex(Pattern);    //创建Regex实类

            textBox2.Text = "";

            //读取文件

            try

            {

                StreamReader sr = new StreamReader(@textBox1.Text,System.Text.Encoding.GetEncoding("GB2312"));

                textstring = sr.ReadToEnd();

                sr.Close();

            }

            catch

            {

                MessageBox.Show("请把test.txt文件拷贝到C:/");

            }

            //根据匹配正值表达式分割字符串

            string[] words = regex.Split(textstring);

            //单词加入哈希表

            foreach (string word in words)

            {

                //textBox2.Text = textBox2.Text + "   " + i;

                if (word != null && word != "")

                {

                    if (ht.Contains(word))

                    {

                        j = Convert.ToInt32(ht[word]) + 1;

                        //ht.Remove(word);

                        //ht.Add(word, j);

                        ht[word]=j;

                    }

                    else

                    {

                        ht.Add(word, 1);

                    }

                }

            }

            对哈希表排序

            ArrayList akeys = new ArrayList(ht.Keys);

                //按字母顺序进行排序

                //akeys.Sort() ;

                //按字单词次数进行排序

                string[] keyarray = new string[akeys.Count];

                int[] valuearray = new int[akeys.Count];

                int index=0;

                //将key/value分别赋给数祖

                foreach (string skey in akeys)

                {

                    keyarray[index] = Convert.ToString(skey);

                    valuearray[index] = Convert.ToInt32(ht[skey]);

                    index++;

                }

                for(int a=0;a<akeys.Count;a++)

                {

                    for (int b = a+1; b < akeys.Count; b++)

                    {

                        if (valuearray[a]>valuearray[b])

                        {

                            valuearray[a] ^= valuearray[b];

                            valuearray[b] ^= valuearray[a];

                            valuearray[a] ^= valuearray[b];

                            string tempstr = keyarray[a];

                            keyarray[a] = keyarray[b];

                            keyarray[b] = tempstr;

                        }

                    }

                }

            //显示

                //按字母顺序进行排序显示

                //foreach(string skey in akeys)

                //{

                //    textBox2.Text = textBox2.Text + skey + "\t" + ht[skey] + "\r\n";

                //}

                //按字单词次数进行排序显示

                for (int a = 0; a < akeys.Count; a++)

                {

                    textBox2.Text = textBox2.Text + keyarray[a] + "\t" + valuearray[a] + "\r\n";

                }

        }

    }

}