关于文件复制的程序代码

这是一个对于文献正片的例程，蓄意有人不妨用上，不必再探求了。#include <stdio.h>#include <sys\stat.h>bool forceexist;const bufsize = 409600; //基础单元为400k//---------------------------------------------------------------------------void __fastcall tform1::formcreate(tobject *sender){   edit1->text = extractfilepath(paramstr(0));}//---------------------------------------------------------------------------void __fastcall tform1::button1click(tobject *sender){   if (opendialog1->execute())   {      ansistring ffile = opendialog1->filename;      ansistring tfile = edit1->text+extractfilename(ffile);      if (copyfile(ffile,tfile))      {             //复制胜利....      }      else {         forceexist = false;         deletefile(tfile);      }   }}//---------------------------------------------------------------------------bool tform1::copyfile(ansistring fromfile,ansistring tofile){   bool result(false);   file *fromf,*tof;   int numread,numwritten;   /* bufsiz is defined in stdio.h */   char buf[bufsize];   screen->cursor = crhourglass;   tof = fopen(tofile.c_str(),"wb");   fromf = fopen(fromfile.c_str(),"rb");   try   {      starttime = now();      struct stat statbuf;      /* get information about the file */      fstat(fileno(fromf), &statbuf);      int modval = statbuf.st_size % bufsize;      int maxval = statbuf.st_size / bufsize;      if (modval) maxval++;      progressbar1->max = maxval;      float fsize = statbuf.st_size;      tvarrec args[2] = {0,fsize};      lblfilesize->caption = format("文献巨细: %.*n字节", args, 1);      lblstarttime->caption = "发端功夫: "+formatdatetime("hh:nn:ss",starttime);      forceexist = false;      progressbar1->position = 0;      do      {         if (progressbar1->position<maxval-1)         {            numread = fread(&buf, sizeof(buf), 1, fromf);   // read the data            numwritten = fwrite(&buf, sizeof(buf), 1, tof); // write the data            fsize = bufsize * (progressbar1->position + 1);         }         else if (modval) {//当结余的数据不及400k时，需作特出处置...            char *smallbuf;            smallbuf = (char *)sysgetmem(modval);            numread = fread(smallbuf, modval, 1, fromf);   // read the data            numwritten = fwrite(smallbuf, modval, 1, tof); // write the data            fsize += modval;            sysfreemem(smallbuf);            numread = 0;         }         progressbar1->position++;         tvarrec args[2] = {0,fsize};         lblfiletrans->caption = format("仍旧复制: %.*n字节", args, 1);         lblelapsetime->caption = "已用功夫: "+formatdatetime("hh:nn:ss",now()-starttime);         application->processmessages();      }      while (!forceexist && (numread!=0 || numread==numwritten));      progressbar1->position++;      fclose(tof);      fclose(fromf);      result = !forceexist;   }   catch(...)   {      fclose(tof);      fclose(fromf);      messagedlg("在复制文献时展示缺点，未能实行操纵。", mtwarning, tmsgdlgbuttons() << mbok, 0);   }   screen->cursor = crdefault;   return result;}//---------------------------------------------------------------------------void __fastcall tform1::btnstopclick(tobject *sender){if (messagedlg("正在复制文献，能否要废除操纵？", mtwarning, tmsgdlgbuttons() << mbyes << mbno, 0)==mryes)   forceexist = true;}//---------------------------------------------------------------------------