asked on

ISAPI DLL's and (yes) VCL objects

Is it possible to create a VCL object, like a TChart, from within an ISAPI DLL, giving it a 'parent' and calling it's methods to save to a graphic file (of course so I can stream the chart, as a jpeg eventually, back to the happy browser)??? Seems we would just need a valid parent for the TChart, and that's the hitch. I.e., can another object be the parent (nil don't work), perhaps some non-visual TForm derivative?? Need an approach here, or even an unrelated solution method.

Thanks, experts. This would be very cool, indeed!

daviscon

ASKER

Ground-breaking? No, just a nice way to do web-based database with graphs...

rwilson032697

Any container VCL object (such as a TForm, TPanel, TGroupBox etc) can be the parent of a TChart component.

You could certainly create a hidden form and use this as the parent of the TChart component.

eg:
var
MyForm : TForm;
MyChart : TChart;
.
MyForm := Application.CreateForm(TForm, MyForm);
MyChart := TChart.Create(MyForm);
MyChart.Parent := MyForm;
// And away you go...

Cheers,

Raymond.

daviscon

ASKER

Tapplication.Createform is not possible since this is a TWebModule and not a TApplication as the defines are different. Your code in an ISAPI WebModule causes this error"

[Error] SPDB.pas(89): Incompatible types: 'TForm' and 'procedure, untyped pointer or untyped parameter'

which indicates that the ISAPIApp and HTTPApp sources for a TWebModule do not support this. I agree that it should be doable, but I don't want to incurr the overhead of including (even if it works, which I'm not sure it would) TApplication just to declare a container object. Maybe what's needed is a container that is 'lighter'...

Thanks for your response. I'll try anything that's suggested with appreciation.

Ed

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rwilson032697

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daviscon

ASKER

Nice work! I had failed in my earlier attempts at identical code to add the line assigning Parent to the chart, thinking Owner would be all that was needed!

Thanks again for a fast and effective response!

Ed