源文件内容：

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace wzy
{
 /// <summary>
 /// Form 的摘要说明。
 /// </summary>
 public class Form : System.Windows.Forms.Form
 {
  private System.Windows.Forms.Label label;

  private System.Windows.Forms.Button button;
  private System.Windows.Forms.Button button;
  private System.Windows.Forms.Button button;

  private System.Windows.Forms.RichTextBox richTextBox;
  private System.Windows.Forms.RichTextBox richTextBox;

  private System.Windows.Forms.OpenFileDialog openFileDialog;
  private System.Windows.Forms.SaveFileDialog saveFileDialog;
 
  /// <summary>
  /// 必需的设计器变量。
  /// </summary>
  private System.ComponentModel.Container components = null;

  public Form()
  {
   //
   // Windows 窗体设计器支持所必需的
   //
   InitializeComponent();

   //
   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
   //
  }

  /// <summary>
  /// 清理所有正在使用的资源。
  /// </summary>
  protected override void Dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null)
    {
     components.Dispose();
    }
   }
   base.Dispose( disposing );
  }

  #region Windows 窗体设计器生成的代码
  /// <summary>
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {
   this.label = new System.Windows.Forms.Label();
   this.button = new System.Windows.Forms.Button();
   this.richTextBox = new System.Windows.Forms.RichTextBox();
   this.button = new System.Windows.Forms.Button();
   this.richTextBox = new System.Windows.Forms.RichTextBox();
   this.openFileDialog = new System.Windows.Forms.OpenFileDialog();
   this.saveFileDialog = new System.Windows.Forms.SaveFileDialog();
   this.button = new System.Windows.Forms.Button();
   this.SuspendLayout();
   //
   // label
   //
   this.label.Location = new System.Drawing.Point(8, 8);
   this.label.Name = "label";
   this.label.Size = new System.Drawing.Size(7, );
   this.label.TabIndex = 0;
   this.label.Text = "词法分析";
   //
   // button
   //
   this.button.Location = new System.Drawing.Point(0, 8);
   this.button.Name = "button";
   this.button.Size = new System.Drawing.Size(6, );
   this.button.TabIndex = ;
   this.button.Text = "分析";
   this.button.Click += new System.EventHandler(this.button_Click);
   //
   // richTextBox
   //
   this.richTextBox.Location = new System.Drawing.Point(, 8);
   this.richTextBox.Name = "richTextBox";
   this.richTextBox.Size = new System.Drawing.Size(0, );
   this.richTextBox.TabIndex = ;
   this.richTextBox.Text = "";
  // this.richTextBox.TextChanged += new System.EventHandler(this.richTextBox_TextChanged);
   //
   // button
   //
   this.button.Location = new System.Drawing.Point(96, 8);
   this.button.Name = "button";
   this.button.Size = new System.Drawing.Size(6, );
   this.button.TabIndex = ;
   this.button.Text = "读入";
   this.button.Click += new System.EventHandler(this.button_Click);
   //
   // richTextBox
   //
   this.richTextBox.Location = new System.Drawing.Point(80, 8);
   this.richTextBox.Name = "richTextBox";
   this.richTextBox.Size = new System.Drawing.Size(80, );
   this.richTextBox.TabIndex = ;
   this.richTextBox.Text = "";
   //
   // button
   //
   this.button.Location = new System.Drawing.Point(8, 8);
   this.button.Name = "button";
   this.button.Size = new System.Drawing.Size(6, );
   this.button.TabIndex = ;
   this.button.Text = "保存";
   this.button.Click += new System.EventHandler(this.button_Click);
   //
   // Form
   //
   this.AutoScaleBaseSize = new System.Drawing.Size(6, );
   this.ClientSize = new System.Drawing.Size(8, 0);
   this.Controls.Add(this.button);
   this.Controls.Add(this.richTextBox);
   this.Controls.Add(this.button);
   this.Controls.Add(this.richTextBox);
   this.Controls.Add(this.button);
   this.Controls.Add(this.label);
   this.MaximizeBox = false;
   this.Name = "Form";
   this.Text = "Form";
  // this.Load += new System.EventHandler(this.Form_Load);
   this.ResumeLayout(false);

  }
  #endregion

  /// <summary>
  /// 应用程序的主入口点。
  /// </summary>
  [STAThread]
  static void Main()
  {
   Application.Run(new Form());
  }
/// <summary>
/// 词法分析函数
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
  private void button_Click(object sender, System.EventArgs e)
  {
   //得到想要的字符数组。
   char[] getch = textToCharArray();

   //将字符数组，转换为词法分析后的　单词数组。
   string[] stringArray = charArrayToStringArray(getch);

   //将单词数组分类，用数字标出各个单词所在的类别。
   string[,] twoStringArray = stringArrayToTwoStringArray(stringArray);

   //用于输出二维数组。
   printString(twoStringArray);

  }
/// <summary>
/// 输出结果　即用于输出二维数组。
/// </summary>
/// <param name="twoStringArray"></param>
  private void printString(string[,] twoStringArray)
  {
   //提示说明
   this.richTextBox.Text =" -> 保留字"  + "\r\n" +
         " -> 运算符"  + "\r\n" +
         " -> 分隔符"  + "\r\n" +
         " -> 数字 "   + "\r\n" +
         " -> 其它"    + "\r\n";
   //输出二维数组中的数据
   for(int x=0;x<twoStringArray.Length/;x++)
   {
    for(int y=0;y<;y++)
    {
     this.richTextBox.Text = this.richTextBox.Text + twoStringArray[y,x] + " ";
     if( y == )
     {
      this.richTextBox.Text = this.richTextBox.Text + "\r\n";
     }
    }
   }
  }

/// <summary>
/// 打开方件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
  private void button_Click(object sender, System.EventArgs e)// 文件打开的方法。
  {
   openFileDialog.Filter = "文本文件(*.txt)|*.txt";
   openFileDialog.Title = "打开要分析的源文件。";

   if(openFileDialog.ShowDialog() == DialogResult.OK)
   {
    System.IO.StreamReader sr = new
     System.IO.StreamReader(openFileDialog.FileName);
    this.richTextBox.Text = sr.ReadToEnd();
    sr.Close();
   }
  }
/// <summary>
/// 保存文件　
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
  private void button_Click(object sender, System.EventArgs e)
  {
   saveFileDialog.Filter = "文本文件(*.txt)|*.txt";
   saveFileDialog.Title = "保存分析结果.";
   if(saveFileDialog.ShowDialog() == DialogResult.OK)
   {
    System.IO.StreamWriter wr = new
     System.IO.StreamWriter(saveFileDialog.FileName);
    wr.Write(this.richTextBox.Text);
    wr.Close();   
   }
  }

/// <summary>
/// 引用二维数组和单词的标志j
/// </summary>
/// <param name="twoArray"></param>
/// <param name="j"></param>
  private void oneArrayToTwo(ref string[,] twoArray,ref int j)
  {
 
   string[,] tempArray = twoArray;
   twoArray = new string[,j+];
   for(int x=0;x<;x++)
   {
    for(int y=0;y<j+;y++)
    {
     twoArray[x,y] = tempArray[x,y];
    }
   }
   j=j+; 
  }
/// <summary>
/// 引用单词数组，和要加入单词数组的单词
/// </summary>
/// <param name="stringArrange"></param>
/// <param name="st"></param>
  private void stringToArrayString(ref string[] stringArrange, string st)
  {

   if(stringArrange[0] =="")
   {
    stringArrange[0] = st;
   }
   else
   {
    string[] oldA = stringArrange;//刚得到的字符串
    int i=oldA.Length +;
    stringArrange = new string[i];//申请一个长一个的字符数组。
    oldA.CopyTo(stringArrange,0);//将先前的字符数组考到现在这个数组中。
    stringArrange[stringArrange.Length -] = st;
   }
  }
/// <summary>
/// 将Text中的字符串，存入一个字符数组中。
/// </summary>
/// <returns></returns>
        private char[] textToCharArray()
  {
   string stringTemp;
   stringTemp = this.richTextBox.Text;
   char[] getch = stringTemp.ToCharArray();//要处理的字符都在getch这个数组中。
   return getch;
  }
/// <summary>
/// 字符数组 到 单词数组
/// </summary>
/// <param name="getch"></param>
/// <returns></returns>
  private string[] charArrayToStringArray(char[] getch)//将字符数组转换为字符串数组。即词法分析后的单词数组。
  {
   string[] stringArrange={""} ;//用这个字符串数组存放词法分析后得到的单词。
   char charTemp;
   string stringSave = "";//  存放一个分析得到的单词

   //一次循环因得到一个单词。
   for(int i = 0;i < getch.Length;i++)
   {
    charTemp = getch[i];
   
    //由字母开头　数字和字母组成的单词。
    if( charTemp >= 'a'&&
     charTemp <= 'z'
     ||
     charTemp >= 'A' &&
     charTemp <= 'Z')
    {
     stringSave = charTemp.ToString();
     i = i + ;
     int test = 0;//判断循环是否结束，　为结束。
     while(test == 0)
     {
      charTemp = getch[i];
      if( charTemp >= 'a'&&
       charTemp <= 'z'
       ||
       charTemp >= 'A' &&
       charTemp <= 'Z'
       ||
       charTemp >= '0' &&
       charTemp <= '9')
      {
       stringSave = stringSave + charTemp.ToString();
       i = i + ;
      }
      else
       test = ;
     }
     stringToArrayString(ref stringArrange,stringSave);
    }
    stringSave = "";
    //由数字组成的单词。
    if( charTemp >= '0' &&
     charTemp <= '9')
    {
     stringSave = stringSave + charTemp.ToString();
     i = i + ;
     int test = 0;
     while(test == 0)
     {
      charTemp = getch[i];
      if( charTemp >= '0' &&
       charTemp <= '9')
      {
       stringSave = stringSave + charTemp.ToString();
       i = i + ;
      }
      else
       test = ;
     }
      stringToArrayString(ref stringArrange,stringSave);
    }
    stringSave = "";
    //由运算符组成的单词。
    if(    charTemp == '+'
     || charTemp == '-'
     || charTemp == '*'
     || charTemp == '/'
     || charTemp == '='
     || charTemp == '<'
     || charTemp == '>'
     || charTemp == '!')
    {
     stringSave = stringSave + charTemp.ToString();
     i = i + ;
     int test = 0;
     while(test == 0)
     {
      charTemp = getch[i];
      if(    charTemp == '+'
       || charTemp == '-'
       || charTemp == '*'
       || charTemp == '/'
       || charTemp == '='
       || charTemp == '<'
       || charTemp == '>'
       || charTemp == '!')
      {
       stringSave = stringSave + charTemp.ToString();
       i = i + ;
      }
      else
       test = ;
     }
     stringToArrayString(ref stringArrange,stringSave);
    }
    stringSave = "";
    //由介符组成的单词。
    if(   charTemp == '('
     ||charTemp == ')'
     ||charTemp == '{'
     ||charTemp == '}'
     ||charTemp == '['
     ||charTemp == ']'
     ||charTemp == ','
     ||charTemp == ':'
     ||charTemp == ';'
     ||charTemp == '"'
     ||charTemp == '\''
     ||charTemp == '\\')
    {
     stringSave = stringSave + charTemp.ToString();
     stringToArrayString(ref stringArrange,stringSave);
    }
   }
   return stringArrange;
  }
/// <summary>
/// 单词数组 到 二维单词数组。
/// </summary>
/// <param name="stringArray"></param>
/// <returns></returns>
  private string[,] stringArrayToTwoStringArray(string[] stringArray)
  {
   //存放单词标识后的结果。
   string [,] twoArray = new string[,];
   //单词的标志
   int j=0;

   //每循环一次，把一个单词归于一类，即前面加上一个数字。
   for(int i=0;i<stringArray.Length;i++)
   {
    //保留字
    if(    stringArray[i] == "main"
     || stringArray[i] == "int"
     || stringArray[i] == "float"
     || stringArray[i] == "printf"
     || stringArray[i] == "if"
     || stringArray[i] == "for"
     || stringArray[i] == "while"
     || stringArray[i] == "do"
     || stringArray[i] == "return"
     || stringArray[i] == "break"
     || stringArray[i] == "continue")
    {
     twoArray[0,j] = "";
     twoArray[,j] = stringArray[i];
     this.oneArrayToTwo(ref twoArray,ref j);
    }
    //运算符
    else
    if( stringArray[i] == "+"
     || stringArray[i] == "-"
     || stringArray[i] == "*"
     || stringArray[i] == "/"
     || stringArray[i] == ">"
     || stringArray[i] == "<"
     || stringArray[i] == ">="
     || stringArray[i] == "<="
     || stringArray[i] == "!="
     || stringArray[i] == "=="
     || stringArray[i] == "++"
     || stringArray[i] == "--"
     || stringArray[i] == "=")
    {
     twoArray[0,j] = "";
     twoArray[,j] = stringArray[i];
     this.oneArrayToTwo(ref twoArray,ref j);
    }
    //分隔符
    else
    if( stringArray[i] == "("
     || stringArray[i] == ")"
     || stringArray[i] == "{"
     || stringArray[i] == "}"
     || stringArray[i] == "["
     || stringArray[i] == "]"
     || stringArray[i] == ","
     || stringArray[i] == ";"
     || stringArray[i] == ":"
     || stringArray[i] == "\""
     || stringArray[i] == "/*"
     || stringArray[i] == "*/")
    {
     twoArray[0,j] = "";
     twoArray[,j] = stringArray[i];
     this.oneArrayToTwo(ref twoArray,ref j);
    }
    //数字
    else
    if( stringArray[i].ToCharArray()[0] >='0' &&
     stringArray[i].ToCharArray()[0] <= '9')
    {
     twoArray[0,j] = "";//数字
     twoArray[,j] = stringArray[i];
     this.oneArrayToTwo(ref twoArray,ref j);
    }
    //其它 (变量等)
    else
    {
     twoArray[0,j] = "";
     twoArray[,j] = stringArray[i];
     this.oneArrayToTwo(ref twoArray,ref j);
    }
   }
   return twoArray;
  }

 }
}