Binding
Binding
The determination of which method in the class
hierarchy is to be invoked for a particular object.
Static (Early) Binding occurs at compile time
When the compiler can determine which method in the
class hierarchy to use for a particular object.
<![CDATA[
Time time1, *tPtr = &time1;
ZonedTime zTime1, *ztPtr = &zTime1;
time1.SetTime(12, 30, 00);
zTime1.SetZonedTime(13, 45, 30);
time1.PrintTime( ); // Time's PrintTime ( ) method
zTime1.PrintTime( ); // ZonedTime's PrintTime( ) method
tPtr->PrintTime( ); // Time's PrintTime( )
ztPtr->PrintTime( ); // ZonedTime's PrintTime( )
]]>
Dynamic (Late) Binding occurs at run time
When the compiler cannot determine the binding of an object to any method.
To indicate that a method is to be bound dynamically,
the class must use the reserved word virtual in the method's prototype.
When a method is defined as virtual, all overriding methods from that point on down the hierarchy are virtual, even if not explicitly defined to be so.
For clarity, explicitly use the virtual reserved word.
Last Modified: Monday, 28-Aug-2006 10:16:04 EDT