Difference between revisions of "DODEFAULT()"

Revision as of 12:44, 7 December 2012

Purpose

Function to call the parent class method from within a sub-class

Syntax

DODEFAULT()

See Also

ACLASS(), ADDPROPERTY(), AMEMBERS(), CLASS, CLASS - Methods, CLASS - Parameters, CLASS - Properties, CLASS - Scoping, COMPOBJ(), CREATEOBJECT(), DEFINE CLASS, DISPLAY CLASSES, FOREACH, LIST CLASSES, LOADOBJECT(), METHOD, NEWOBJECT(), OBJECT(), PRINT_HTML(), PRINT_JSON(), PRINT_R(), PRINT_XML(), REMOVEPROPERTY(), REQUIRE_ONCE(), SAVEOBJECT(), SQL SELECT, WITH

Description

The DODEFAULT() function is used to call the parent class method from within a sub-class. It can only be used within a class method. It calls the parent class method of the same name as the calling method. It allows a sub-class to perform the default parent class behavior along with additional behavior specific to that particular sub-class.

Example

class Box 
  procedure Draw 
    messagebox("This is the parent Draw Method") 
  endproc && Draw 
endclass 
 
class Dialog1 of Box 
  procedure Draw 
    messagebox("This is the object Draw Method")
    // call the Draw method of the Box parent class
    dodefault() 
  endproc && Draw 
endclass 
 
oDIALOGOK = createobject("Dialog1")
oDIALOGOK.Draw()
release oDIALOGOK

Products

Lianja Server, Lianja