How can I check variable is defined or not in ColdFusion

Question

I want a if condition in ColdFusion which is check #firstWordCategory# variable is defined or not.

Answer 1

Every variable will be in some scope and scope(mostly) is simply a structure.

So, you can use structKeyExists() like this:

<!--- If your variable is in VARIABLES scope --->
<cfif structKeyExists(VARIABLES, "firstWordCategory")>

    <!--- Your Code --->

</cfif>

Answer 2

To check any variable existence you can use isDefined function:

<cfif isDefined("firstWordCategory")>
    <cfoutput>#firstWordCategory#</cfoutput>
</cfif>

For more check this.