topic ?= in Application Development and Automation Discussions

?=

former_member637135 — Fri, 18 May 2007 08:46:37 GMT

what is functionality of ?= in the below statement....

LOOP AT lt_relations INTO li_relation.

ls_agent-agent ?= cl_obl_interface_factory=>binrel_agent(

ii_relation = li_relation ).

ls_agent-binrel = li_relation.

COLLECT ls_agent INTO lt_agent.

ENDLOOP.

plz help me.

Thanks,

Regards.

Re: ?=

uwe_schieferstein — Fri, 18 May 2007 09:02:29 GMT

Hello

'?=' is the casting from one reference type to another.

Method CL_OBL_INTERFACE_FACTORY=>BINREL_AGENT returns the most generic reference type, i.e. OBJECT.

Using ?= this generic object is casted into the more specific object type of ls_agent-agent (presumably CL_BINARY_RELATION).

Regards

Uwe

Re: ?=

Former Member — Fri, 18 May 2007 10:10:27 GMT

Hi,

Go through the below sample code to understand about casting...

REPORT Z_ABAPOBJECTS_CAST.

----

CLASS C1 DEFINITION

----

CLASS C1 DEFINITION.

PUBLIC SECTION.

data: var1 type ref to object.

METHODS: METH1.

ENDCLASS. "C1 DEFINITION

----

CLASS C1 IMPLEMENTATION

----

CLASS C1 IMPLEMENTATION.

METHOD METH1.

WRITE: / 'This is a method one'.

ENDMETHOD. "METH1

ENDCLASS. "C1 IMPLEMENTATION

----

CLASS C2 DEFINITION

----

CLASS C2 DEFINITION inheriting from c1.

PUBLIC SECTION.

METHODS: METH2.

ENDCLASS. "C2 DEFINITION

----

CLASS C2 IMPLEMENTATION

----

CLASS C2 IMPLEMENTATION.

METHOD METH2.

WRITE: / 'This is a method two'.

ENDMETHOD. "METH2

ENDCLASS. "C2 IMPLEMENTATION

START-OF-SELECTION.

DATA REF1 TYPE REF TO C1.

DATA REF2 TYPE REF TO C2.

DATA REF3 TYPE REF TO C2.

CREATE OBJECT REF2.

ref1 = ref2.

ref3 ?= ref1.

Regards,

Azaz Ali.