How to make CalendarExtender before ModalPopupExtender?

Question

How to make CalendarExtender extending TextBox placed inside ModalPopupExtender to show before ModalPopupExtender?

Answer 1

Add this javascript bit to your page:

    function calendarShown(sender, args)
    {
        sender._popupBehavior._element.style.zIndex = 10005;
    }

And then in the attributes for your calendar expander add:

OnClientShown="calendarShown"

Answer 2

My CSS solution:

.ajax__calendar_container
{
    position: relative;
}

Answer 3

Updating the Ajax library also resolved this issue.