save a file to a TBlobStream and read it back

// To save a file to BLOB:
procedure TForm1.Button1Click(Sender: TObject);
var
blob: TBlobStream;
begin
blob := yourDataset.CreateBlobStream(yourDataset.FieldByName('YOUR_BLOB'), bmWrite);
try
blob.Seek(0, soFromBeginning);
fs := TFileStream.Create('c:\your_name.doc', fmOpenRead or
fmShareDenyWrite);
try
blob.CopyFrom(fs, fs.Size)
finally
fs.Free
end;
finally
blob.Free
end;
end;
// To load from BLOB:

procedure TForm1.Button1Click(Sender: TObject);
var
blob: TBlobStream;
begin
blob := yourDataset.CreateBlobStream(yourDataset.FieldByName('YOUR_BLOB'), bmRead);
try
blob.Seek(0, soFromBeginning);

with TFileStream.Create('c:\your_name.doc', fmCreate) do
try
CopyFrom(blob, blob.Size)
finally
Free
end;
finally
blob.Free
end;
end;

{
Using this code you can work with any database engine (BDE/ADO/DAO/ODBC/etc)
and any file format (document of MS Word, spreadsheet of MS Excel, bitmap or
jpeg pictures, wav-files etc)
}

Compact and Repair an Access Database

uses
ComObj;

function CompactAndRepair(DB: string): Boolean; {DB = Path to Access Database}
var
v: OLEvariant;
begin
Result := True;
try
v := CreateOLEObject('JRO.JetEngine');
try
V.CompactDatabase('Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+DB,
'Provider=Microsoft.Jet.OLEDB.4.0;Data Source='+DB+'x;Jet OLEDB:Engine Type=5');
DeleteFile(DB);
RenameFile(DB+'x',DB);
finally
V := Unassigned;
end;
except
Result := False;
end;
end;

add a Row Number in your DBGrid

{+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1. create new blank field in dbgrid
2. rename the title with 'No'
3. put this code in OnDrawColumncell
4. Now your Grid has a row number
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++}

procedure TForm1.DBGrid1DrawColumnCell(Sender: TObject; const Rect: TRect;
DataCol: Integer; Column: TColumn; State: TGridDrawState);
begin
if DataSource1.DataSet.RecNo > 0 then
begin
if Column.Title.Caption = 'No' then
DBGrid1.Canvas.TextOut(Rect.Left + 2, Rect.Top, IntToStr(DataSource1.DataSet.RecNo));
end;
end;

create an Access Database

uses
ComObj;

procedure TForm1.Button1Click(Sender: TObject);
var
AccessApp: Variant;
begin
AccessApp := CreateOleObject('Access.Application');
AccessApp.NewCurrentDatabase('c:\111.mdb');
AccessApp := Unassigned;
end;

color a specific (conditional) cell in a DBGrid

procedure TFRM_Main.DBG_MainGetCellParams(Sender: TObject; Field: TField;
AFont: TFont; var Background: TColor; Highlight: Boolean);
begin

if (Field.AsString = '0') and (Field.FullName = 'LoadingAttn') then
begin
Background := $00E69B00;
AFont.Color := clBlack;
AFont.Style := AFont.Style + [fsBold];
end
else
begin
if (Field.AsString = '0') and (Field.FullName = 'DeliveryAttn') then
begin
Background := $0082FFFF;
AFont.Color := clBlack;
AFont.Style := AFont.Style + [fsBold];
end
else
begin
if (Field.AsString = 'H') and (Field.FullName = 'EctaCode1') then
begin
Background := $008080FF;
AFont.Color := clBlack;
AFont.Style := AFont.Style + [fsBold];
end
else
begin
AFont.Color := clBlack;
AFont.Style := AFont.Style - [fsBold];
Background := clWhite;
end;
end;
end;


end;