Crystal Reports Custom IsNull Function
Solution 1
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}
Solution 2
I found this issue, in the formula editor there is a drop down in the header that indicates:
- Exception for Nulls
- Default values for nulls
Select the second one ( Default values for nulls)
Solution 3
I've encountered the same behavior, but I have yet to see a documented reason for this.
I would suggest that you use a SQL Expression:
//{%myField}
(
ISNULL({myField},'Hello World')
)
Solution 4
This worked for me:
if (isnull({dbvalue}) or ({dbvalue} ='')) then
"Display the required text"
else
{dbvalue}
JPVoogt
South African Data Tinkerer and @Microsoft Fanboy | Johannesburg Data Platform Leader | Formula 1 enthusiast and Father | (He/Him)
Updated on January 30, 2020Comments
-
JPVoogt over 4 years
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?