VB中Implements的作用Implements [InterfaceName | Class] VB6中的面向对象编程---实现类继承 确切地说VB6不能实现真正意义上的类继承(如C++中的继承),但是通过其关键字Implements也提供了类似的功能。 Implements [InterfaceName | Class] VB6中的面向对象编程---实现类继承 确切地说VB6不能实现真正意义上的类继承(如C++中的继承),但是通过其关键字Implements也提供了类似的功能。 我们先建一个类模块CBase.cls 代码如下:
CODE: Private mvarBaseProperty As String Public Sub BaseFunction() MsgBox “Hello world!” End Sub Public Property Let BaseProperty(ByVal VData As String) mvarBaseProperty = VData End Property Public Property Get BaseProperty() As String BaseProperty = mvarBaseProperty End Property 接下来我们新建一类模块(Cinherit.cls),代码如下,其间有关键的注释 CODE: Implements CBase '注意此关键字 Dim m_BaseProperty As String '--------------------------------------------------------------------- '虚线间的代码即是从CBase类继承的. '注意其格式如下:基类_属性名(或方法名) '其方法的声明关键字public也变为了private Private Property Get CBase_BaseProperty() As String BaseProperty = m_BaseProperty End Property Private Property Let CBase_BaseProperty(ByVal VData As String) m_BaseProperty = VData End Property Private Sub CBase_BaseFunction() MsgBox "Inherit" End Sub '--------------------------------------------------------------------- '此方法是继承类自己的方法 Public Sub InheritMsg() MsgBox "my owner msg" End Sub 现在我们新建一窗体来做测试,我们把测试代码放在Form_Load事件中 测试一: CODE: Dim objTest As CBase Set objTest = New CBase With objTest .BaseFunction End With Set objTest = Nothing 运行程序,弹出base,说明是调用Cbse中的BaseFunction函数 测试二: CODE: Dim objTest As CBase Set objTest = New CInherit With objTest .BaseFunction End With Set objTest = Nothing 运行程序,弹出Inherit,说明是调用Cinherit中的Base函数 测试三: CODE: Dim objTest As CInherit Set objTest = New CInherit With objTest .InheritMsg End With Set objTest = Nothing 运行程序,弹出my owner function,说明继承的类可以使用自己的函数或属性 |
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