Newbie question - how to check for a varible

Mark Schonewille m.schonewille at economy-x-talk.com
Fri May 8 02:40:57 EDT 2009


Hi Stephen,


Search the docs for "empty". It will show you things like

put empty into x
set the cProp to empty

So, you will also want to read up on "put" and "set".

There is also a function "variableNames", which will probably be very  
useful to you. Why do you want to check for the existence of a  
variable? I do this very, very rarely and only in really advanced  
projects.


--
Best regards,

Mark Schonewille

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On 8 mei 2009, at 08:25, Stephen Cox wrote:

> Really two questions:
>
> How do I check if a variable is empty? Sort of like;
>
> If !empty(tUsername)
>    // process here
> Endif
>
> Empty() is a Foxpro function that pops if what you are checking is  
> empty. I
> can’t seem to find it’s equivalent in revolution. Am I approaching  
> this the
> wrong way? And can I check fields the same way?
>
> I suppose I could create an empty variable and just compare the 2?  
> But is
> there an easier way?
>
> Next question; checking the existence of a variable? Now I know I  
> can turn
> on Strict Compilation (and I have) but I’d rather have the assurance  
> of
> checking to see if a variable exist? Is this a non-issue in  
> Revolution?
>
> Thanks
>
> -Stephen Cox




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