ARTICLE
iXML Library - Down Casts
For reference variables with the static type of the interfaces
IF_IXML_... in iXML Library, the usual
down casts with the
casting operators
?= and
CAST can be used for
assignments from more general to more specific types. If a down cast
fails, the exception CX_SY_MOVE_CAST_ERROR is raised, which can
be handled in a TRY control structure (as usual).
The method QUERY_INTERFACE of the interface
IF_IXML_UNKNOWN (implemented by
every object in iXML Library) can be used to make handling of
exceptions simpler:
special_reference ?= general_reference- query_interface( type ).
type can be used to specify the required special type by
specifying a constant ixml_iid... from the type group
IXML . A successful down cast runs
as if no method is called. If an error occurs, the exception is handled
in the method and an initial reference returned.
Example
See iXML Library, Down Casts
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved