Crystal Reports Custom IsNull Function

function crystal-reports crystal-reports-2008
JPVoogt picture JPVoogt · Aug 13, 2012 · Viewed 75.4k times · Source

I am trying to create a custom IsNull Function in Crystal Reports; the function must act the same way as the IsNull Function in MS SQL Server. I want to specify a field, and if the field is null, then it must be returned with a value I have specified.

IsNull({myField},0) or
IsNull({myField},'Hello World')

I have encountered that I have to create a separate function for number fields and a separate function for text fields. I also found that Crystal does not allow the use of standard functions inside of a custom function, for instance the ISNULL Function:

Function(NumberVar param, Numbervar setter)
IF ISNULL(param) THEN setter ELSE param

and

Function(StringVar param, StringVar setter)
IF param = NULL THEN setter ELSE param

Does anyone know how I can create a function like this in Crystal and a work around for the ISNULL inside of a custom function?

Answer

dotjoe picture dotjoe · Aug 13, 2012

You can't pass a null value into a custom function, so it's pointless to use crystal's isnull function inside one. Only option is to write it like...

if isnull({myField}) then 0 else {myField}

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