自己写一个简单的C++单词扫描程序。[1]

/******************************************/
/* file:unit2.h (scan.h)                  */
/* a scanner for lexical analysis for c++ */
/* author:zhanjiantao(compower)           */
/******************************************/
#include <vcl.h>
#define maxno 48
typedef struct typetoken
{
  int line;
  ansistring words;
  ansistring type;
}atoken;
typedef atoken *listnd;

class scan
{
public:
        bool isreserveword(ansistring token);
        void initrw();
        void doscan(char *infile);
        void print(int lineno, ansistring stoken, int strgrdl, ansistring type);
        void maketl(int line,ansistring words,ansistring type);
        void compress(char *zipfname);
public:
        char *file;
        char ch;
        ansistring strtoken;
        ansistring reservews[maxno];
        tlist *tokenlist;
        listnd anode;
};

#endif

/******************************************/
/* file:unit2.cpp (scan.cpp)              */
/* a scanner for lexical analysis for c++ */
/* author:zhanjiantao(compower)           */
/******************************************/
#include "unit2.h"
#include <string.h>
#include <fstream.h>
//initiate reserved words list
void scan::initrw()
{
     const int buflen = 10;
     char buf[buflen];
     ansistring gotword = "";
     ifstream inirw("initrw.ini");
     int i = 0;
     while(inirw.getline(buf,buflen))
     {
      gotword = buf;
      reservews[i++] = gotword;
     }
     inirw.close();
     tokenlist = new tlist;
}

//judge the ch in the rw list or not
bool scan::isreserveword(ansistring token)
{
  bool result = false;
  int low = 0;
  int high = maxno-1;
  while(low<=high)
  {
    int mid = (low + high)/2;
    int rscomp = token.ansicompare(reservews[mid]);
    if(rscomp==0)
    {
      result = true;
      break;
    }
    if(rscomp<0)
    {
      high = mid-1;
    }
    else
    {
      low = mid+1;
    }
  }
  return result;
}

//print on stringgrid
void scan::print(int lineno, ansistring stoken, int strgrdl, ansistring type)
{
   form1->stringgrid1->rowcount++;
   form1->stringgrid1->cells[0][strgrdl] = lineno;
   form1->stringgrid1->cells[1][strgrdl] = stoken;
   form1->stringgrid1->cells[2][strgrdl] = type;
}

//make a token list
void scan::maketl(int line,ansistring words,ansistring type)
{

   anode = new atoken;
   anode->line = line;
   anode->words = words;
   anode->type = type;
   tokenlist->add(anode);
}

//scan--the hardcore of the scanner
void scan::doscan(char *infile)
{
   file = infile ;
   ifstream scanfile(file);

   int linecount = 1;         //the word in which line
   strtoken = "";           //member of class scan
   int strgrdline = 1;       //temp var for show result on stringgrid

   const int bflength = 254;  //length of getline buffer
   char buffer[bflength];     //getline buffer