IsCustomFunction  
Description
Determines whether a name represents a custom function.
 
Returns
True, if name can be called as a custom function; False, otherwise.
 
Category
Decision functions
 
Function syntax
IsCustomFunction(name)
 
Parameters
 
Parameter      Description
name Name of a custom function. Must not be in quotes. If not a defined variable or
  function name, ColdFusion generates an error.
 
Usage
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.
Note: To prevent undefined variable exceptions, always precede IsCustomFunction with an IsDefined test, as shown in the example.
 
Example
<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>
name  
Name of a custom function. Must not be in quotes. If not a defined variable or function name, ColdFusion generates an error.