How to determine which button is clicked in enter paramter values screen

Hi,
I am using VB 6.0 code and trying to invoke crystal reports 8.5.0.217
When I invoke crystal report using crystal report object it shows me "Enter Parameters screen" to enter the parameters for reports. This screen has two buttons - OK and Cancel. Clicking Ok should generate report which is working fine but when I click Cancel button, even then blank report is getting generated without any data.

Please help me regarding this so that I can close the report or remove the crystal report object once the Cancel button is clicked. I want to know how to determine that which button is clicked in "Enter Parameter Screen".

When I use VB6 (or any other language) normally I ask for the parameters inside the VB6 application and send them to the CR report or the user can decide to cancel the report and don't display anything
When CR ask for the parameters it is already running and you can't stop (afaik)