I'd like to use a UDF in this property to convert an empty value of a date type into null value.

Thought VFP help says "use ConversionFunc to specify native Visual FoxPro or CUSTOM conversion functions...", it is not working with a simple function like this:

Function ChangeNull(tdData)
If tdData = {}
Return null
Else
Return tdDAta
EndIf
EndFunc


I set the CA property like this:

.ConversionFunc = "date_field ChangeNull"


"set procedure" is ok too...


What's wrong? Shouldn't it work?