【PB】TriggerEvent()/Event()/PostEvent()有什么不同

电玩女神 2022-06-18 05:52 153阅读 0赞

TriggerEvent()/Event()/PostEvent()有什么不同

在PB中经常要从一个事件中调用另外一个事件，常用的就是这几个函数

event把被调用事件放在最后面处理，可以带参数，也可以返回值，dynamic event()是其经典用法

注：Dynamic表示编译时指定事件可以不存在，系统把返回值类型检查推迟，到应用程序运行时进行。

triggerEvent触发指定对象的指定事件，是在事件队列的当前位置插入指定的事件，并且立即执行该事件中的脚本，它只能返回1，-1 或者空，带了long,word也比较麻烦

PostEvent在事件队列最后追加指定的事件，不是立即执行

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**In PowerBuilder, there are several types of events.**  
System events with an ID:User actions or other system messages or a call in your scripts

System events without an ID:

User-defined events with an ID:User actions or other system messages or a call in your scripts

User-defined events without an ID:A call in your scripts

\-----  
objectname.**TriggerEvent** ( event \{, word, long \} )

Triggers an event associated with the specified object, which executes the script for that event immediately.

**Return value**  
Integer.  
Returns 1 if it is successful and the event script runs and -1 if the event is not a valid event for objectname, or no scriptexists for the event in  objectname. If any argument's value is null, TriggerEvent returns null.

**Usage**  
If you specify the name of an event instead of a value of the TrigEvent enumerated datatype, enclose the name in doublequotation marks.

\-----  
objectname.**PostEvent** ( event, \{ word, long \} )

Adds an event to the end of the event queue of an object.

**Return value**  
Boolean.  
Returns true if it is successful and false if the event is not a valid event for objectnameobjectname. Also returns true ifno script exists for the event in objectname. If any argument's value is null, PostEvent returns null.

**Usage**  
You cannot post events to the event queue for an application object. Use TriggerEvent instead.

PowerBuilder messages or a call in your scripts