Validate Time portion of date/time control in a form

rule with formula like this should work

equals(formatDate(StartDate,'hhtt'),'12AM')‍

note it will only validate when date portion is filled as well.

Sure you can check for any hour you want.

But I do not get what you mean 'input to hhtt'

It's a format string that directs formatDate() function to return hour and AM/PM flag out of supplied date, so ithas always to be there in that form.

this worked for me, but i have another question related to time portion only

how to validate "Meeting Requested Time" to be >= 5 hours from the current time, which is the form submission time?

the "Meeting Requested Time" is a named control for Date/time field

thank you for your reply, i tried the DateFiffHours, it didnt calculate the correctly coz it consider the CurrentDate time as 12:00AM all the time

it didnt consider the real current time

I created my formula as:

dateDiffHours(new date(),RequestDate)

the when i previewed the form i got the error msg:

{The form is reporting the following errors:
NWF.RuntimeFunction.date.call is not a constructor}

and the calculated value didn't display any thing

any thing i missed here?

dateDiffHours(new Date (),RequestDate)

wooow, worked as a charm,

thank you so much, i was struggling everywhere to get it done

please let me know 2 things:

1- how to mark this as a solution

2- what is the "new Date" function? it was not listed any where, and where can i find a reference for these kind of functions?

once again many thanks 

equals(formatDate(StartDate,'hhtt'),'12AM')

How can I specify a time range? Say from 601PM - 859AM.