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Vassiliev I solved my problem, thank you on your time and effort, I 
really appreciate your help and your advices.

Thank you very much,
Tomislav


Vassiliev V. V. wrote:
> May be field is not TBlobField? Check type of ADOQuery1->FieldByName("IMG"). 
> Try also TBlobField->SaveToStream() instead of create TBlobStream, or use 
> ADOQuery1->CreateBlobStream() instead of create TBlobStream - dbGo (ADO 
> components) have own TADOBlobStream and are probably incompatible with 
> TBlobStream.
> 
> //------------------------------------------
> Regards,
> Vassiliev V. V.
> http://www.managed-vcl.com - using .Net objects in Delphi for Win32 +
> ADO.Net
> http://www.oledbdirect.com - The fastest way to access MS SQL Server,
> MS Jet (Access) and Interbase (through OLEDB)
> 
> 
> 
> "Tomislav Hundric'" <rifnet@gmail.com> �������/�������� � �������� 
> ���������: news:46ab8171@newsgroups.borland.com...
>> Again I want to thank you Vassiliev,
>> I did what you suggested, and I save .jpg images from my app to db using 
>> following onClick button event:
>>
>>   if (OpenPictureDialog1->Execute())
>>   {
>>     ADOQuery1->Edit();
>>     TBlobField* field = (TBlobField*)ADOQuery1->FieldByName("FIELDNAME");
>>     field->LoadFromFile(OpenPictureDialog1->FileName);
>>     ADOQuery1->Post();
>>   }
>>
>> and this works as expected, no errors and when I open db in ms access I 
>> can confirm that picture has been saved (it says Long Binary Data). 
>> However I still get error "Invalid class typecast" when I try to load 
>> image, I've tried to google for this error and I didn't find any solutions 
>> or workarounds for this problem. I've searched through 
>> borland.public.cppbuilder.graphics news group and there was mentioned that 
>> this solution should work, but for some reason which is enigma to me my 
>> app breaks at:
>>
>> TBlobStream* stream = new TBlobStream(field, bmRead);
>>
>> I don't know if you can help me with this one, I really appreciate your 
>> help so far.
>>
>> Thanks in advance,
>> Tomislav.
>>
>>
>>
>> Vassiliev V. V. wrote:
>>> Access saves not only jpeg file but also ActiveX information. So if you 
>>> save jpeg from your program and load it later it will work, but save jpeg 
>>> from Access UI and load will not work (jpeg should be stored in BLOB with 
>>> some offset, for bitmap offset was 78 if I am not wrong but it is not 
>>> constant), and save jpeg from your program will not allow to view it from 
>>> Access UI. You may look for third-party components to save BLOBs in 
>>> format compatible with Access UI. However if you do not need Access UI 
>>> just work with BLOBs as from any other DBMS.
>>>
>>> //------------------------------------------
>>> Regards,
>>> Vassiliev V. V.
>>> http://www.managed-vcl.com - using .Net objects in Delphi for Win32 +
>>> ADO.Net
>>> http://www.oledbdirect.com - The fastest way to access MS SQL Server,
>>> MS Jet (Access) and Interbase (through OLEDB)
>>>
>>>
>>> "Tomislav Hundric'" <rifnet@gmail.com> �������/�������� � �������� 
>>> ���������: news:46ab24f1@newsgroups.borland.com...
>>>> Hi Vassiliev,
>>>> thanks on your quick response. I'm sorry if I'm asking too much, but am 
>>>> I doing it right, I create blank database and table with two fields, ID 
>>>> (autonumber) and IMG(OLE OBJECT), for starters I'm filling IMG field via 
>>>> MS Access, so I right click on IMG field and select Insert Object... 
>>>> Create from file and then I choose .jpg file which I want to add. In 
>>>> c++builder 6, I have a form with dbImage and button:
>>>>
>>>> I've included:
>>>> #include <jpeg.hpp>
>>>>
>>>> and register class on form create event:
>>>> DBImage1->Picture->RegisterFileFormat(__classid(TJPEGImage), "jpg", 
>>>> "JPEG File", __classid(TJPEGImage));
>>>>
>>>> DBImage control AutoDisplay property is set to false, and on buttonClick 
>>>> event I have:
>>>>
>>>>     TBlobField* field = (TBlobField*)ADOQuery1->FieldByName("IMG");
>>>>     TBlobStream* stream = new TBlobStream(field, bmRead);
>>>>     TJPEGImage* image = new TJPEGImage;
>>>>     DBImage1->Picture->Assign(image);
>>>>     DBImage1->Picture->Graphic->LoadFromStream(stream);
>>>>     delete stream;
>>>>     delete image;
>>>>
>>>> When I click on button, I get error "Invalid class typecast", I can't 
>>>> figure out what's wrong, can you tell me if this approach is ok, or I 
>>>> should do it in some other way.
>>>>
>>>> Thanks in advance,
>>>> Tomislav.
>>>>
>>>>
>>>> Vassiliev V. V. wrote:
>>>>> Access (Jet engine) does support BLOBs. Just in MS Access UI you will 
>>>>> see it not as OLE object but as binary data (i.e. can not normally view 
>>>>> in MS Access UI). Inside your application it will be normal BLOB as in 
>>>>> most other DBMS.
>>>>>
>>>>> //------------------------------------------
>>>>> Regards,
>>>>> Vassiliev V. V.
>>>>> http://www.managed-vcl.com - using .Net objects in Delphi for Win32 +
>>>>> ADO.Net
>>>>> http://www.oledbdirect.com - The fastest way to access MS SQL Server,
>>>>> MS Jet (Access) and Interbase (through OLEDB)
>>>>>
>>>>>
>>>>> "Tomislav Hundric" <rifnet@gmail.com> �������/�������� � �������� 
>>>>> ���������: news:46aaee61@newsgroups.borland.com...
>>>>>> Hi,
>>>>>> I have the following situation. I have to develop application that 
>>>>>> will be used to display images and data from db. My first thought was 
>>>>>> I'll use ms access db because it is very simple to deploy, only one 
>>>>>> file and the best part is I don't have to install bde engine since it 
>>>>>> uses microsoft jet driver which is native in windows, but since ms 
>>>>>> access doesn't have blob field I have to use OLE object and I found 
>>>>>> out that it converts jpeg images to bmp and increases size of db 
>>>>>> dramatically. I know I can use save the path to file in db field and 
>>>>>> then retrieve the image stored locally, but this is not a good 
>>>>>> solution to me since I'll be storing hundreds of images so I want to 
>>>>>> avoid hundreds of files stored locally. My next thought was to use 
>>>>>> paradox db since it is able to store images in blob field, but I want 
>>>>>> to avoid installation of bde if possible. I've came across this 
>>>>>> article which says:
>>>>>>
>>>>>> Jet 4.0 supports connections to Paradox 3, 4 and 5 only; we do not 
>>>>>> support later versions. The ADO connection string syntax would be:
>>>>>>
>>>>>> cnn.Open "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data
>>>>>> Source=c:\somepath;" & _ "Extended Properties=Paradox 5.x;"
>>>>>>
>>>>>> I've tried the connection string above and I get error:
>>>>>> Could not find installable ISAM
>>>>>>
>>>>>> Does anyone know is it possible to connect to paradox db using jet 
>>>>>> drivers (ADO Connection), or can anyone suggest me which is the best 
>>>>>> way to solve my problem.
>>>>>>
>>>>>> Thanks in advance,
>>>>>> Tomislav
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