Determines whether a name represents a custom function.

True, if name can be called as a custom function; False, otherwise.

Decision functions

IsCustomFunction(name)

The IsCustomFunction function returns True for any function that can be called as a custom function, including functions defined using CFScript function declarations and cffunction tags, and functions that are ColdFusion component methods. For CFC methods, you must first instantiate the component.

<h3>IsCustomFunction Example</h3>
<cfscript>
function realUDF() {
   return 1;
}
</cfscript>
<cfset X = 1>

<!--- Example that fails existence test --->
<cfif IsDefined("Foo") AND IsCustomFunction(Foo)>
   Foo is a UDF.<br>
</cfif>

<!--- Example that passes existence test but fails IsCustomFunction --->
<cfif IsDefined("X") AND IsCustomFunction(X)>
   X is a UDF.<br>
</cfif>

<!--- Example that passes both tests--->
<cfif IsDefined("realUDF") AND IsCustomFunction(realUDF)>
   realUDF is a function.<br>
</cfif>

<!--- Example using a CFC, defined in TestCFC.cfc--->
<cfobject component="TestCFC" name="myTestCFCobject">
<CFIF IsDefined("myTestCFCobject.testFunc") AND 
      IsCustomFunction(myTestCFCobject.testFunc)>
   myTestCFCobject.testFunc is a function.
</CFIF>