main.cpp

AbsDataBase5.16 最新版

//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop

#include "Main.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma link "ABSMain"
#pragma resource "*.dfm"
TfrmMain *frmMain;

const AnsiString DataBaseFileName = "../../Data/Demos.abs";

//---------------------------------------------------------------------------
__fastcall TfrmMain::TfrmMain(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TfrmMain::FormCreate(TObject *Sender)
{
  dbDemos->Close();
  dbDemos->DatabaseFileName = ExtractFilePath(Application->ExeName) + DataBaseFileName;
  dbDemos->Open();
  tPhotoAlbum->Open();
}
//---------------------------------------------------------------------------

void __fastcall TfrmMain::btLoadImageClick(TObject *Sender)
{
TFileStream *FileStream;
TStream *BlobStream;

 if (odBlob->Execute())
   {
     tPhotoAlbum->Edit();
     try
     {
       BlobStream = tPhotoAlbum->CreateBlobStream(tPhotoAlbum->FieldByName("Photo"),bmWrite);
       FileStream = new TFileStream(odBlob->FileName,fmOpenRead+fmShareDenyNone);
       BlobStream->CopyFrom(FileStream,FileStream->Size);
       delete FileStream;
       delete  BlobStream;
       tPhotoAlbum->Post();
       tPhotoAlbumAfterScroll(tPhotoAlbum);
     }
     catch(...)
     {
       tPhotoAlbum->Cancel();
     }
   }
}
//---------------------------------------------------------------------------

void __fastcall TfrmMain::btSaveImageClick(TObject *Sender)
{
TFileStream *FileStream;
TStream *BlobStream;

  if (sdBlob->Execute())
    {
      FileStream = new TFileStream(sdBlob->FileName,fmCreate);
      BlobStream = tPhotoAlbum->CreateBlobStream(tPhotoAlbum->FieldByName("Photo"),bmRead);
      FileStream->CopyFrom(BlobStream,BlobStream->Size-BlobStream->Position);
      delete BlobStream;
      delete FileStream;
    };
}
//---------------------------------------------------------------------------

void __fastcall TfrmMain::tPhotoAlbumAfterScroll(TDataSet *DataSet)
{
TJPEGImage *JpegImage;
TStream *BlobStream;

  if (!tPhotoAlbum->FieldByName("Photo")->IsNull)
    {
      BlobStream = tPhotoAlbum->CreateBlobStream(tPhotoAlbum->FieldByName("Photo"),bmRead);
      JpegImage = new TJPEGImage;
      try
      {
        JpegImage->LoadFromStream(BlobStream);
        Photo->Picture->Assign(JpegImage);
        Photo->Visible = True;
      }
      __finally
      {
        delete JpegImage;
        delete BlobStream;
      };
    }
  else
    Photo->Visible = False;
}
//---------------------------------------------------------------------------