Assignment when a value is of a specific class

[wriedmann]

Hi Chris,
if I remember correctly, there is an operator or expression that lets me assign a value to a variable when it is of a specific type.
Normally I write:

Code: Select all

if oValue is MyClass
  oClass := oValue
endif

But I was not able to find anything in the help....
Wolfgang

[Chris]

Hi Wolfgang,

If you have (in the Core dialect) :

LOCAL oValue AS OBJECT
LOCAL oClass AS MyClass

then you can do:

oClass := (MyClass) oValue

or

oClass := oValue ASTYPE MyClass

or you can totally replace the local declaration and put it in the IS pattern instead:

IF oValue IS MyClass VAR oClass
? oClass:ToString()
ENDIF

[wriedmann]

Hi Chris,
thank you very much!
I was searching this form:

Code: Select all

oClass := oValue ASTYPE MyClass

because when using

Code: Select all

oClass := (MyClass) oValue

and oValue is of another type I will see a runtime exception.
Wolfgang
P.S. this is from a code piece where I need to traverse JSON values