Constraint for date/time

Support
1

Hello, could anyone tell me whether or not it is possible to create a
constraint in XLSForms that uses variables from the current time?

For example:

  • User inputs a number into an integer field, but if it is more than 2
    hours different from the current time, there is an input validation error.
  • User inputs a year into an integer field, but if it is more than 10 years
    different from the current year (2017), there is an input validation error.

Thanks in advance!

2

This behavior is a little tricky, but here goes...

now() will give you a timestamp and you'll need to wrap it with once()
if you don't want the form to constantly re-evaluate it. Once you have that, you
can use format-date-time(${now_string}, '%H') to grab the hour and
format-date-time(${now_string}, '%Y') to grab the year. You then use
those in the constraints.

I've attached an example. If the behavior is not what you want, try
removing the once() part.

Yaw

datetime_constraint.xlsx (11 KB)

ยทยทยท On Wed, Jan 18, 2017 at 9:50 AM, wrote: > Hello, could anyone tell me whether or not it is possible to create a > constraint in XLSForms that uses variables from the current time? > > For example: > > - User inputs a number into an integer field, but if it is more than 2 hours > different from the current time, there is an input validation error. > - User inputs a year into an integer field, but if it is more than 10 years > different from the current year (2017), there is an input validation error. > > Thanks in advance! > > -- > -- > Post: opendatakit@googlegroups.com > Unsubscribe: opendatakit+unsubscribe@googlegroups.com > Options: http://groups.google.com/group/opendatakit?hl=en > > --- > You received this message because you are subscribed to the Google Groups > "ODK Community" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to opendatakit+unsubscribe@googlegroups.com. > For more options, visit https://groups.google.com/d/optout.
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