Name

IsDefined

Synopsis

                  
                  IsDefined('variable_name')

Determines if the specified variable exists. Returns true if the specified variable exists or false if it doesn’t. Note that IsDefined( ) replaces the deprecated ParameterExists( ) function. Examples: 

<cfset MyVar="Variable">
<cfset Form.MyFormVar="Form Variable">
   
<cfoutput>
<cfif IsDefined('MyVar')>
  Variable MyVar exists:<br> MyVar = #MyVar#
<cfelse>
  No variable called MyVar exists.
</cfif>
<p><cfif IsDefined('MyFormVar')>
  Variable MyFormVar exists:<br> MyFormVar = #MyFormVar#
<cfelse>
  No variable called MyFormVar exists.
</cfif>
<p><cfif IsDefined('Queryname.field')>
  Variable Queryname.Field exists:<br> QueryName.Field = #Queryname.Field#
<cfelse>
  No variable called Queryname.Field exists.
</cfif>
</cfoutput>

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