asked on

how to show image from db else than save it to file?

Now i'm saving pictures in temp.jpg after that i'm showing them in image1.picture
the code is:

procedure TForm8.DBGrid1CellClick(Column: TColumn); //NUOTRAUKOS RODYMAS
begin
Labelededit1.Text := AdoQuery1.fieldbyname('id').Value;

AdoQuery2.SQL.Clear;
AdoQuery2.SQL.Add('Select picture from klientai where id = '+ Labelededit1.Text +'');
AdoQuery2.Open;

if not TBlobField(AdoQuery2.FieldByName('picture')).IsNull then //is there a picture?
begin
TBlobField(AdoQuery2.fieldbyname('picture')).SaveToFile('Temp.jpg');
Image1.Picture.LoadFromFile('Temp.jpg');
Image1.visible := true;
end
else
begin
Image1.Picture.Bitmap.Assign(Nil); //there is no Image
Image1.visible := false;
end;
end;

I don't want to save them in file, how else i can do it?

ASKER CERTIFIED SOLUTION

BlackTigerX

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BlackTigerX

forgot to mention, make sure you add jpeg to the uses clause

Ivanov_G

// here is DBImage component which works with Bitmap and JPG. You can easily add support for GIF

unit GIDBImage;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
ExtCtrls, DB, DBCtrls, JPEG;

type
TGIDBImage = class(TImage)
private
{ Private declarations }
FDataLink : TFieldDataLink;
function GetDataField: String;
function GetDataSource: TDataSource;
function GetField : TField;
procedure SetDataField(const Value: String);
procedure SetDataSource(const Value: TDataSource);
procedure DataChange (Sender : TObject);
protected
{ Protected declarations }
procedure Loaded; override;
procedure CMGetDataLink (var Message : TMessage); message CM_GETDATALINK;
procedure Notification (AComponent : TComponent; Operation : TOperation); override;
procedure LoadPicture; virtual;
public
{ Public declarations }
constructor Create (AOwner : TComponent); override;
destructor Destroy; override;
property Field : TField read GetField;
published
{ Published declarations }
property DataField : String read GetDataField write SetDataField;
property DataSource : TDataSource read GetDataSource write SetDataSource;
end;

procedure Register;

implementation

procedure Register;
begin
RegisterComponents('GI Data-Aware', [TGIDBImage]);
end;

{ TGIDBImage }

procedure TGIDBImage.CMGetDataLink(var Message: TMessage);
begin
Message.Result := Integer(FDataLink);
end;

constructor TGIDBImage.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
ControlStyle := ControlStyle + [csReplicatable];
FDataLink := TFieldDataLink.Create;
FDataLink.Control := Self;
FDataLink.OnDataChange := DataChange;
end;

procedure TGIDBImage.DataChange(Sender: TObject);
begin
if FDataLink.Field <> nil then
LoadPicture
else
Picture.Graphic := nil;
end;

destructor TGIDBImage.Destroy;
begin
FDataLink.Free;
FDataLink := nil;
inherited Destroy;
end;

function TGIDBImage.GetDataField: String;
begin
Result := FDataLink.FieldName;
end;

function TGIDBImage.GetDataSource: TDataSource;
begin
Result := FDataLink.DataSource;
end;

function TGIDBImage.GetField: TField;
begin
Result := FDataLink.Field;
end;

procedure TGIDBImage.Loaded;
begin
inherited Loaded;
if (csDesigning in ComponentState) then DataChange(Self);
end;

procedure TGIDBImage.Notification(AComponent: TComponent;
Operation: TOperation);
begin
inherited Notification(AComponent, Operation);
if (Operation = opRemove) and (FDataLink <> nil) and (AComponent = DataSource) then
DataSource := nil;
end;

procedure TGIDBImage.SetDataField(const Value: String);
begin
FDataLink.FieldName := Value;
end;

procedure TGIDBImage.SetDataSource(const Value: TDataSource);
begin
FDataLink.DataSource := Value;
if Value <> nil then Value.FreeNotification(Self);
end;

procedure TGIDBImage.LoadPicture;
var
IsJPG : Boolean;
JPG : TJpegImage;
MemStream : TMemoryStream;
begin
// load the picture
// check if the field is BLOB
if not Field.IsBlob then
begin
Picture.Graphic := nil;
Exit;
end;
// determine the type
with Field as TBlobField do
begin
IsJPG := Pos('JFIF', Copy(Value, 1, 10)) > 0;
end;
// if it is Bitmap - load it and exit
if not IsJPG then
begin
Picture.Assign(Field);
Exit;
end;
// load the JPG with MemoryStream
MemStream := TMemoryStream.Create;
JPG := TJPEGImage.Create;
try
TBlobField(Field).SaveToStream(MemStream);
MemStream.Seek(soFromBeginning, 0);
// load the JPG and assign it
JPG.LoadFromStream(MemStream);
Picture.Assign(JPG);
finally
JPG.Free;
MemStream.Free;
end;
end;

end.