get_message_tupleT_get_message_tupleGetMessageTupleGetMessageTupleget_message_tuple (算子名称)

名称

get_message_tupleT_get_message_tupleGetMessageTupleGetMessageTupleget_message_tuple — Retrieve a tuple associated with the key from the message.

参数签名

描述

get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple retrieves a tuple associated with the KeyKeyKeyKeykeykey from the message denoted by the MessageHandleMessageHandleMessageHandleMessageHandlemessageHandlemessage_handle. The tuple has to be previously stored to the message using set_message_tupleset_message_tupleSetMessageTupleSetMessageTupleSetMessageTupleset_message_tuple.

该算子 returns the data in the parameter TupleDataTupleDataTupleDataTupleDatatupleDatatuple_data. The data including strings is copied by the operation, the message can thus be immediately reused.

If the given KeyKeyKeyKeykeykey is not present in the message or if the data associated with the key is not a tuple, get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple fails. Presence of keys and information about the data associated with the key can be verified using get_message_paramget_message_paramGetMessageParamGetMessageParamGetMessageParamget_message_param.

运行信息

• 多线程类型:可重入(与非独占操作符并行运行)。
• 多线程作用域:全局(可以从任何线程调用)。
• 未经并行化处理。

参数表

例程 (HDevelop)

* ...
get_message_param (Message,'key_exists',['simple_string','foo','my_image'],\
                   KeysPresence)
get_message_param (Message,'key_data_type',['simple_string','my_image'],\
                   KeysType)
get_message_tuple (Message,'simple_string',TupleString)

结果

If the operation succeeds, get_message_tupleget_message_tupleGetMessageTupleGetMessageTupleGetMessageTupleget_message_tuple returns 2 ( H_MSG_TRUE) . Otherwise an exception is raised. Possible error conditions include invalid parameters (handle or key), the required key not found in the message, or other than tuple data associated with given key.

可能的前置算子

dequeue_messagedequeue_messageDequeueMessageDequeueMessageDequeueMessagedequeue_message

可替代算子

get_message_objget_message_objGetMessageObjGetMessageObjGetMessageObjget_message_obj

参考其它

create_messagecreate_messageCreateMessageCreateMessageCreateMessagecreate_message, clear_messageclear_messageClearMessageClearMessageClearMessageclear_message, set_message_tupleset_message_tupleSetMessageTupleSetMessageTupleSetMessageTupleset_message_tuple, set_message_objset_message_objSetMessageObjSetMessageObjSetMessageObjset_message_obj, get_message_objget_message_objGetMessageObjGetMessageObjGetMessageObjget_message_obj, set_message_paramset_message_paramSetMessageParamSetMessageParamSetMessageParamset_message_param, get_message_paramget_message_paramGetMessageParamGetMessageParamGetMessageParamget_message_param, enqueue_messageenqueue_messageEnqueueMessageEnqueueMessageEnqueueMessageenqueue_message, dequeue_messagedequeue_messageDequeueMessageDequeueMessageDequeueMessagedequeue_message

模块

Foundation

---