$msgid
Return the identifier for a message received from postmessage.
$msgid
Example: putmess " message id =%%$msgid"
Return Values
| Value | Meaning |
|---|---|
| "" | Empty string (""), if the
asynchronous event was not sent by postmessage; $result
indicates the source of the message. |
| >0 | Message identifier, if the
receiveMessage trigger was activated by a
postmessage statement; $result is "message".
|
Use
Allowed only in the receiveMessage trigger of components.
Allowed in all component types except self-contained Report and Services.
Message Handling
The following example shows the receiveMessage trigger for an application. The example assumes that MSG_HANDLER is an instance of a service which contains operations for processing asynchronous messages. It also assumes that MSG_HANDLER has already been created (probably in the apStart trigger as the application started).
trigger receiveMessage
if ( $result = "message" )
putmess "%%$msgdst received from %%$msgsrc"
putmess " message id =%%$msgid"
putmess " message text=%%$msgdata"
if ( $msgid != "Ack")
postmessage $msgsrc, "Ack", "Acknowledging message %%$msgid"
else
if ( $msgid = "A" ) activate "MSG_HANDLER".A ($msgdata)
if ( $msgid = "B" ) activate "MSG_HANDLER".B ($msgdata)
...
endif
else
if ( $result = "Close" ) activate "MSG_HANDLER".CLOSE
if ( $result = "Timeout" ) activate "MSG_HANDLER".TIMEOUT
else
putmess "%%$instancename received unexpected async message: %%$result"
endif
end; receiveMessage
