这是一个关于文件拷贝的例程，希望有人可以用上，不用再摸索了。



#include <stdio.h>

#include <sys\stat.h>





bool ForceExist;

const bufsize = 409600; //基本单位为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))

      {



             //复制成功....

      }

      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("文件大小: %.*n字节", args, 1);

      lblStartTime->Caption = "开始时间: "+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) {//当剩余的数据不足400K时，需作特殊处理...

            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("已经复制: %.*n字节", args, 1);

         lblElapseTime->Caption = "已用时间: "+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("在复制文件时出现错误，未能完成操作。", mtWarning, TMsgDlgButtons() << mbOK, 0);

   }

   Screen->Cursor = crDefault;

   return result;

}

//---------------------------------------------------------------------------

void __fastcall TForm1::BtnStopClick(TObject *Sender)

{

if (MessageDlg("正在复制文件，是否要取消操作？", mtWarning, TMsgDlgButtons() << mbYes << mbNo, 0)==mrYes)

   ForceExist = true;

}

//---------------------------------------------------------------------------