Date validation in pop up form

[nrmarthi]

Hello guys

I had developed report which, pop up form and i have StartDate and EndDate in form

the MiniCalendar is use to input date in these.
Now i want to validate both dates

StartDate should noot be Null
EndDate should not be Null and less than StartDate

I searched for similar information for help. couldn't find

Can anyone help me

Thank you