怎样用FileStream往文件结尾填充指定字节的空白？

Question

procedure TForm1.Button1Click(Sender: TObject);
var
  TmpStream,DataStream : TFileStream ;
begin
  TmpStream := TFileStream.Create('c:\test.txt' ,fmCreate);
  DataStream := TFileStream.Create('c:\bak.txt',fmOpenRead);
  TmpStream.CopyFrom(DataStream,DataStream.Size);
  TmpStream.Write('def',length('def'));
  DataStream.Free;
  TmpStream.Free;
end;取代了代码中的def，换成空格即可

Answer 1

不知道用fillchar函数行不行？

Answer 2

A、分配一段内存
B、写文件
C、释放内存procedure AppendBlank(const sFileName; String; Count: Integer);
var
  Stream: TFileStream;
  Buf: PByte;
begin
  Stream := TFileStream.Create(sFileName, fmReadWrite);
  Stream.Seek( 0, 2 ); 
  GetMem( Buf, Count );
  FillChar( Buf^, Count, 0 );
  Stream.Write( Buf^, Count );
  FreeMem( Buf );
  Stream.Free;
end;