Using ListAppend and dynamic variables

[mmcarthey]

Hello all,

I have an example that is causing me trouble.

If I do the following, things work as expected.

CODE:

<cfoutput query="Customers">

<cfset var2 = listAppend(var2, #Customers.accno#)>

</cfoutput>

OUTPUT: #var2#

RESULTS: 553,610

The problem is that my output changes unexpectedly if I change my code.

CODE:

<cfoutput query="Customers">

<cfset var#Customers.key# = listAppend(var#Customers.key#, #Customers.accno#)>

</cfoutput>

OUTPUT: var#Customers.key#

RESULTS: var2,610

For a reason I haven't been able to determine, the ListAppend (or simple concatenate for that matter) is pre-pending the name of the dynamic variable to the list.  I can only assume it is the manner in which ColdFusion evaluates the statement but I'm not sure how to work around it.

Thanks for any help!

[ilssac]

CODE:

<cfoutput query="Customers">
     <cfset variables["var" & Customers.key] = listAppend(variables["var" & Customers.key], variables.Customers.accno)>
</cfoutput>

Array notation is a much more reliable way to work with dynamic variable naming.

[mmcarthey]

I don't believe I've seen the variables[] array.  Is that a built-in construct?

I'm assuming there's some magic there since without it the code functions just as in my original post.

Thanks

[ilssac]

mmcarthey wrote:

I don't believe I've seen the variables[] array.  Is that a built-in construct?

I'm assuming there's some magic there since without it the code functions just as in my original post.

Thanks

Yes, starting with CF 6, when ColdFusion was ported to a Java base, all the scopes of ColdFusion are structure arrays, including the variables[] scope which is where unscoped variables live.

[Adam Cameron.]

<cfoutput query="Customers">

<cfset var#Customers.key# = listAppend(var#Customers.key#, #Customers.accno#)>

</cfoutput>

Which version of CF were you able to get that code to run?

The <cfset> line has two syntax errors in it: both reverences to the dynamic variable you're trying to create are invalid, and will not compile on any version of CF I know of.

??

--

Adam