Empty fields and controls after testing

Ken Ray kray at sonsothunder.com
Wed Oct 26 16:43:09 CDT 2011


On Oct 26, 2011, at 11:19 AM, Bob Sneidar wrote:

> Yes, you will need to write your own initialization routine. I do this anyway in all my forms because I read data into the fields, and then validate before writing them back to my storage. I always want to make sure I do not have any random data from a previous edit session making it's way into my database. Usually I have a populate handler that when passed empty for the arguement instead of a string or array, it puts empty into all my fields. Then I just call the populate handler when I open the form, typically in preOpenCard. 


One thing to be careful about - NEVER do this (unless you are 100% sure):

on preOpenCard
  repeat with x = 1 to the number of fields
    put empty into field x
  end repeat
end preOpenCard

It seems reasonable, but what it will do is to empty out your label fields as well, which can be a real PITA to put back again. It's always better (IMHO) to either address the fields you want to clear *directly*, like:

on preOpenCard
  put "FirstName,LastName,Age" into tFields
  repeat for each item tField in tFields
    put empty into field tField
  end repeat
end preOpenCard

OR, set some kind of custom property on the fields you want to clear (or protect), or at least make sure you walk carefully on fields that have their lockText turned on (which is what label fields have by default), like:

on preOpenCard
  repeat with x = 1 to the number of fields
    if the lockText of field x is false then
      if the short name of field x is not among the items of "PrefilledField, DefaultCity" then
        put empty into field x
      end if
    end if
  end repeat
end preOpenCard

Just my 2 cents…

Ken Ray
Sons of Thunder Software, Inc.
Email: kray at sonsothunder.com
Web Site: http://www.sonsothunder.com/	



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