lang_classes

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.