I like using CF's "short circuit" logic (introduced in 4.5, I think?) like
this:
<CFIF IsDefined("variable") AND Len(Variable)>
#variable#
</CFIF>
Evaluation is sequential in the CFIF. This way, you only show the variable
if it exists and is not empty. Something similar can be done with numbers:
<CFIF IsDefined("variable") AND IsNumeric(Variable)>
#variable#
</CFIF>
Or make sure the number is not zero:
<CFIF IsDefined("variable") AND IsNumeric(Variable) AND Variable>
#variable#
</CFIF>
Etc...
Chris Lofback
Sr. Web Developer
TRX Integration
28051 US 19 N., Ste. C
Clearwater, FL 33761
www.trxi.com
-----Original Message-----
From: Justin Scott [mailto:[EMAIL PROTECTED]]
Sent: Monday, June 03, 2002 3:36 PM
To: CF-Talk
Subject: Re: if value exists, show it
Hi Trey!
> I simply want to test to see if a variable has a value (eg text has been
> returned from a query) and if so, show it. There seem to be a few
options --
>
> <cfif isdefined(#variable#)>
> #variable#
> </cfif>
As Raymond already pointed out, isDefined() takes a string as the input and
returns a boolean that tells if the variable exists or not. This will
return true even if the string is empty. There is no locking required
specifically for isDefined().
> <cfif len(#variable#) GT 0>
> #variable#
> </cfif>
This assumes the variable exists and will output its contents if it is not
empty (sounds closest to what you want). This could be better written
simply as..
<cfif len(variable)>
> <cfif #variable# IS "">
> #variable#
> </cfif>
This will not do much, since you're displaying the string if it IS empty.
If you changed the operator to IS NOT or NEQ it would act just like the
len() does above. I would presonally prefer using len() in this case.
-Justin Scott, Lead Developer
Sceiron Internet Services, Inc.
http://www.sceiron.com
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