GetCheckedRows method only available for ISRowChecker or AllowMultipleSelection scenario.
So, there is no way if you turn off ISRowChecker escpecially in server side.
I think there is another workaround for you in client side. You will need to use ISRowchecker and set display syle "none" in checkbox Column header element (via client side) .
With this way, you still can access GetCheckedRows method in server or client. Hope this helps.

Regards,
Handy

Hi Handy,

Is there a sample to do this?

Regards,

Madhavan

Hi Madhavan,

You only need to get the element of header checkbox and set none to display style. I think i have showed you how to get element of checkbox at the past.

Regards,
Handy