TStream.Size Property

Indicates the size in bytes of the stream.

Pascal

property Size: Int64;

C++

__property Int64 Size;

Description

Use Size to find the size of the stream. Size is used internally in routines that read and write to and from the stream. Setting the Size property of TStream does nothing. Some descendants of TStream override this property to allow applications to change the size of the resource accessed using the stream.

C++ Examples:

Copy Code

/*
This example reads any file and converts the encoding to UTF8.
This example uses the TBytesStream to read the files into a TBytes'
and also uses the auto_ptr construction to clean up created class
instances.

*/
#include <tchar.h>
#include <memory>       //for STL auto_ptr class
//---------------------------------------------------------------------------

#pragma argsused
int _tmain(int argc, _TCHAR* argv[])
{
  // Sample to convert a file of any encoding to UTF8.
  TEncoding *LEncoding = NULL;
  std::auto_ptr<TFileStream> LFileStream(new TFileStream("..\\Sample.txt", fmOpenRead));

  // Read file into buffer
  TBytes myBytes;
  std::auto_ptr<TBytesStream> myBytesStream(new TBytesStream(myBytes));
  myBytesStream->CopyFrom(LFileStream.get(), LFileStream->Size);

  // Identify encoding and convert buffer to UTF8
  int LOffset = TEncoding::GetBufferEncoding(myBytesStream->Bytes, LEncoding);
  if (LOffset == 0)
    return 1; // Unknown encoding, don't convert.
  myBytes = TEncoding::Convert(LEncoding, TEncoding::UTF8,
                               myBytesStream->Bytes,
                               LOffset, myBytesStream->Size-LOffset);
  // Create output file
  std::auto_ptr<TFileStream> DestFileStream(new TFileStream("..\\SampleUTF8.txt", fmCreate));

  // Write UTF8 byte order mark and buffer to output file
  TBytes LByteOrderMark;
  LByteOrderMark = TEncoding::UTF8->GetPreamble();

  // Grab preamble and write to destination
  DestFileStream->Write(&LByteOrderMark[0], LByteOrderMark.Length);

  // Write converted buffer
  DestFileStream->Write(&myBytes[0], myBytes.Length);
  return 0;
}

Delphi Examples:

Copy Code

{
This example determines the encoding of a source file and then
writes the file in any encoding chosen.  Use this project to
create files of any encoding.  This example requires two text edits
and a combobox.
}
procedure TForm1.Button1Click(Sender: TObject);
var
  LBuffer: TBytes;
  LByteOrderMark: TBytes;
  LOffset: Integer;
  LEncoding, DestEncoding: TEncoding;
  LFileStream: TFileStream;
  EncodingArray: array[0..5] of TEncoding;
begin
  LEncoding:= nil;
  EncodingArray[0]:= TEncoding.UTF8;
  EncodingArray[1]:= TEncoding.UTF7;
  EncodingArray[2]:= TEncoding.Unicode;
  EncodingArray[3]:= TEncoding.Default;
  EncodingArray[4]:= TEncoding.BigEndianUnicode;
  EncodingArray[5]:= TEncoding.ASCII;
  DestEncoding := EncodingArray[ComboBox1.ItemIndex];
  LFileStream := TFileStream.Create(Edit1.Text, fmOpenRead);
  try
    // Read file into buffer
    SetLength(LBuffer, LFileStream.Size);
//    LFileStream.Read(LBuffer[0], Length(LBuffer));
    LFileStream.ReadBuffer(Pointer(LBuffer)^, Length(LBuffer));

    // Identify encoding and convert buffer to UTF8
    LOffset := TEncoding.GetBufferEncoding(LBuffer, LEncoding);
//    for I := 0 to Length(LBuffer) - 1 do
//      Memo1.Lines.Add((LBuffer[I]));
    LBuffer := LEncoding.Convert(LEncoding, DestEncoding, LBuffer,
      LOffset, Length(LBuffer) - LOffset);
  finally
    LFileStream.Free;
  end;

  LFileStream := TFileStream.Create(Edit2.Text, fmCreate);
  try
    // Write an encoding byte order mark and buffer to output file
    LByteOrderMark := DestEncoding.GetPreamble;
    LFileStream.Write(LByteOrderMark[0], Length(LByteOrderMark));
    LFileStream.Write(LBuffer[0], Length(LBuffer));
  finally
    LFileStream.Free;
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  StringList: TStrings;
begin
  StringList := TStringList.Create;
  try
    with StringList do begin
      Add('TEncoding.UTF8');
      Add('TEncoding.UTF7');
      Add('TEncoding.Unicode');
      Add('TEncoding.Default');
      Add('TEncoding.BigEndianUnicode');
      Add('TEncoding.ASCII');
    end;
    with ComboBox1 do begin
      Items.Assign(StringList);
      ItemIndex := 0;
    end;
  finally
    StringList.free;
  end;
end;