Message object

The Message object is used to process events that are not defined by PowerBuilder, to communicate parameters between windows when you open and close them, and to specify whether optional parameters are used in TriggerEvent or PostEvent.

You can also customize your own version of the Message object by defining a class user object inherited from the built-in Message object.

For more information about creating a custom Message object, see the chapter on user objects in the PowerBuilder User’s Guide.

Properties

The first four properties of the Message object correspond to the first four properties of the Microsoft Windows message structure:

Message property	Datatype	Description
Handle	Long	The handle of the window or control.
Number	UnsignedInt	The number that identifies the event (this number comes from Windows).
WordParm	Long	The word parameter for the event (this parameter comes from Windows). The parameter’s value and meaning are determined by the event.
LongParm	Long	The long parameter for the event (this number comes from Windows). The parameter’s value and meaning are determined by the event.
ClassDefinition	PowerObject	An object of type PowerObject containing information about the class definition of the object or control.
DoubleParm	Double	A numeric or a numeric variable.
StringParm	String	A string or a string variable.
PowerObjectParm	PowerObject	Any PowerBuilder object type including structures.
Processed	Boolean	A boolean value set in the script for the user-defined event or the Other event. Values are: TRUE – The script processed the event; do not call the default window process (DefWindowProc) after the event has been processed. FALSE – (Default) Call DefWindowProc after the event has been processed.
ReturnValue	Long	When Message.Processed is true, specifies the value you want returned to Windows. This property is ignored when Message.Processed is false.

Events

Message event	Occurs
Constructor	When the user object is created.
Destructor	When the user object is destroyed.

Functions

Message function	Datatype returned	Description
ClassName	String	Returns the name assigned to the user object.
GetContextService	Integer	Creates a reference to a context-specific instance of the specified service.
GetParent	PowerObject	Returns a reference to the name of the parent object.
PostEvent	Boolean	Adds an event to the end of the message queue of the user object.
TriggerEvent	Integer	Sends an event to the user object and executes the script associated with the event.
TypeOf	Object	Returns the type of the user object.