面试题：Visual Basic中继承与多态性的基础应用

Question

在Visual Basic中，定义一个基类`Animal`，包含`Name`属性和`MakeSound`方法。然后创建两个子类`Dog`和`Cat`继承自`Animal`，并重写`MakeSound`方法分别输出狗叫和猫叫。请编写完整代码实现上述功能。

Answer 1

' 定义基类Animal
Public Class Animal
    Private _name As String
    ' Name属性
    Public Property Name() As String
        Get
            Return _name
        End Get
        Set(ByVal value As String)
            _name = value
        End Set
    End Property
    ' MakeSound方法
    Public Overridable Sub MakeSound()
        Console.WriteLine("动物发出声音")
    End Sub
End Class

' 定义子类Dog继承自Animal
Public Class Dog
    Inherits Animal
    Public Overrides Sub MakeSound()
        Console.WriteLine("汪汪汪")
    End Sub
End Class

' 定义子类Cat继承自Animal
Public Class Cat
    Inherits Animal
    Public Overrides Sub MakeSound()
        Console.WriteLine("喵喵喵")
    End Sub
End Class

' 测试代码
Module Module1
    Sub Main()
        Dim myDog As New Dog()
        myDog.Name = "小狗"
        myDog.MakeSound()

        Dim myCat As New Cat()
        myCat.Name = "小猫"
        myCat.MakeSound()
    End Sub
End Module