ColdBox3.8.0/CF10 - Checking for RC/PRC variables

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1

Hi,

I am trying to check for a variable in the view that may or may not have been defined in the handler. Whether I used “isDefined” or “valueExists”; I still get variable is undefined in RC/PRC. Am I missing something?

`

<cfif #prc.qSystems.RecordCount# gt “0”>

`

2

isDefined() and valueExists() evaluates a string.

if youre working with dynamic variable names, youll have to eval the variable before using those functions.

3

Not sure I’m following… i thought using isDefined() is to evaluate whether the variable exists or not.

4

I see you’ve tried these things:

<cfif isDefined(#rc.searchValue#)>
<cfif not event.valueExists(rc.searchValue)>
<cfif #prc.qSystems.RecordCount# gt “0”>

May I suggest these instead. As a general rule, you should avoid “isDefined()”. To check for your search string and whether you should search or not:

<cfif structKeyExists(rc, ‘searchValue’) AND len(rc.searchValue) GT 0>

<cfif prc.qSystems.RecordCount GT 0>

I’m guessing you might be relatively new to Coldfusion. I mention that because new folks sometimes tend to over use the # signs. Typically, a variable can be referenced without it, unless used as an attribute.

<cfif qQuery.RecordCount GT 0>
vs.

I have been told that even the attribute use doesn’t need it, however, I always feel like I’m violating good HTML standards, even though CFML is not HTML. As you’re learning, try it without quotes and # signs first, just to see what you can get away with!

Also, if you had to build your variable name and didn’t know it. Like maybe you have myVar_1, myVar_2, etc. You can do this:
<cfif structKeyExists(rc, ‘myVar_#counter#’)> (Assuming a counter variable from some loop.)

5

You can’t pass the actual variable into those function, or of course it will error trying to resolve them. The variable name needs to be quoted as a string.

<cfif isDefined( ‘rc.searchValue’ )>

<cfif not event.valueExists( ‘searchValue’ )>

Thanks!

~Brad

ColdBox Platform Evangelist
Ortus Solutions, Corp

E-mail: brad@coldbox.org
ColdBox Platform: http://www.coldbox.org
Blog: http://www.codersrevolution.com

6

Yes CaptainPalapa, I am brandnew to ColdFusion and ColdBox. I’ve been told to master ColdFusion first before diving into ColdBox, but with time constraint, I have to try and learn both. Thank you for all the good tips!

I appreciate everyone’s patience with my elementary questions.