Determines whether a name represents a custom function.
IsCustomFunction(name)
Parameter |
Description |
|---|---|
name |
Name of a custom function. Must not be in quotation marks. If not a defined variable or function name, ColdFusion generates an error. |
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, first instantiate the component.
Note: To prevent undefined variable exceptions, always precede IsCustomFunction with an IsDefined test, as shown in the example.
Note: This function does not return true if the function was defined using a function expression, eg:
return 1;
}
For functions defined using function expressions, use isClosure().
<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>
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