The function %OpenRefToObject asks the
system for accessing Object Values which are defined with Unique Identifier HOBJ.
Declaration
BOOL %OpenRefToObject(
HBJ in _hbj,
BOOL in _bSynchro
)
Parameters
_hbj
Value of the HBJ type or INT type.
_bSynchro
Value of the Boolean type.
Description
The function allows to ask the system for accessing Object Values which are defined with
Unique Identifier HOBJ.
The values are accessed to all ESL scripts which are
interpreted in the actual process (D2000 HI or D2000 EventHandler) by this function.
The using of this function is recommended in the case that the object (its
HOBJ is mentioned when the function is called) is not directly in the script
and the system do not know automatically, that Object Values are required
for the script.
Example
If the User Tag U.Test (value type Integer) has HOBJ 1234 then the following
script will generate the run-time error (_ERR_OBJECT_NOT_FOUND) or the local
variable _val will be incorrect:
INT _val
ALIAS _a
SET_a AS (1234)
; incorrect row
_val:= _a
The user can avoid this status by using this function %OpenRefToObject(IN HBJ _hbj, IN BOOL _bSynchro):
BOOL _openOk
INT _val
ALIAS _a
SET _a AS (1234)
_openOk:= %OpenRefToObject(_a\HBJ,@TRUE)
IF _openOk THEN
;the row is correct
_val:= _a
ELSE
;an object with HOBJ 1234 does not exist !!!
ENDIF
The parameter _bSynchro is set on @TRUE. This setting allows
to check through the return value of the function if the object with the
required HOBJ exists. The first calling of the function in actual process
communicates with the process D2000 Server synchronously. The existence of
the object is checked. This activity can run some time. If the object exists
then next calling is quick.
If the parameter is set on @FALSE the script
will send the request for opening the object and will proceed. The return value of
the function is @TRUE and that is why it is not possible to check the
existence of the object with defined HOBJ.
Note
If the script do not ask for Object Value the system is
informed by the function %CloseRefToObject.
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