About Calendar control

[snath]

When I pick a date, the Calendar closes; but if I changed my mind and decided not to pick a date, the Calendar remains open. Then, I have to go back on the browser and come back in again to close the Calendar.
How do I close a Calendar pop-up control without picking a date in .NET
I am thinking of clicking anywhere on the screen to have the Calendar close or is there any other way?

[PeOfEo]

This can't be done with just .net. It will require javascript to open and close the window. But I suggest not using javascript for accessibility reasons.