Class definitions
A class definition is the implementation of object oriented structures
within the HBasic language. A class definition may define the following
substructures that can be used local to a class instance:
- variables local in the class
- properties that define methods to set or get the property value
- methods that may access variables of a class instance
- events that may be triggered in the class methods
<class-declaration>
::=
Class <classname>
<class-body>
End Class
<classname>
::= identifier
Create new class
You can create a new class instance with the <New-statement>.
Example: Define class c1 and create Instance of it
Class c1
... Definition of methods, properties ...
End Class
' create global instance of class c
Dim gc As c
Sub button1_clicked()
gc = New c()
End Sub
<class-body> ::=
{
<class-statement>
}
<class-statement>
::=
<dim-statement>
|
<event-declaration>
|
<property-declaration>
|
<sub-declaration>
Example: ex_classes
<Property
declaration> ::=
Property
identifier
As
<typedesc>
[
<Get-property-desc>
]
[
<Let-property-desc>
]
End Property
<Get-Property-desc>
::=
Get
<statementlist>
End Get
<
Let-Property-desc> ::=
Let
<statementlist>
End Let
<Event
declaration> ::=
Event
identifier (
<parameterlist>
)
<Raise-statement> ::=
Raise
event-name( <expr-list> )
where event-name is the name of an event that has been
defined in an <Event declaration>. The <Raise-statement>
may only be used within the Class description which means in a method
between
Class ... End Class.