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"melk" <NOSPAMi_melk@libero.it> wrote in message
news:4242c7fd@newsgroups.borland.com...

> I have to write out to the ASP page directly a JPEG byte array,

There are several steps you have to do in order for that to work.

1) prepare a VARIANT that contains a SAFEARRAY that contains the raw bytes

2) set the IResponse::ContentType property to "image/jpeg".

3) call IResponse::AddHeader() to add an additional "Content-Length" header
value.

4) pass the VARIANT to IResponse::BinaryWrite().

> first I tried to looking for a Method of IRepsonse Interface
"ContentStream"
> that I saw use in Delphi code but i can't find it in BC++ 6...

There is no such property/method in IResponse.  The Delphi code must have
been using something else.

> this method accept a Stream type like one that exit from
TJPEGImage::SaveToStream..

You are probably looking at code realted to the Indy library
(http://www.indyproject.org).  That has nothing to do with ASP programming.

> finaly I tried to use IResponse::binaryWrite without effect, it
> doesn't write on the page..

BinaryWrite() is what you need to use.  You probably just did not set it up
properly.  Try the following code:

    #include <memory>

    {
        Response->Clear();
        Response->put_Buffer(VARIANT_TRUE);

        try
        {
            std::auto_ptr<TMemoryStream> MemStream(new TMemoryStream);
            JPEGImage->SaveToStream(MemStream.get());

            SAFEARRRAYBOUND bounds = {0, MemStream->Size-1};

            TVariant v;
            v.parray = ::SafeArrayCreate(VT_UI1, 1, &bounds);
            v.vt = VT_ARRAY|VT_UI1;

            if( v.parray == NULL )
                throw Exception("Cannot create the array of bytes");

            void *data = NULL;
            if( FAILED(::SafeArrayAccessData(v.parray, &data)) )
                throw Exception("Cannot access the array of bytes");

            memcpy(data, MemStream->Memory, MemStream->Size);
            ::SafeArrayUnaccessData(v.parray);

            Response->put_Status(WideString("200 OK"));
            Response->put_ContentType(WideString("image/jpeg"));
            Response->AddHeader(WideString("Content-Length"),
WideString(IntToStr(MemStream->Size)));
            Response->BinaryWrite(v);
        }
        catch(const Exception &e)
        {
            Response->Clear();
            Response->put_Status(WideString("500 " + e.Message));
        }

        Response->Flush();
    }


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