VB.Net Overloads的实例

代码如下：

乐博网lob.cn提示：调试环境为 vs2005 +  windows2003 / windows2008 / xp / vista

Public Class OverloadsForm
    Dim mianji As OverFather

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        mianji = New OverFather
        Dim r As Single = CSng(InputBox("求圆面积，输入半径"))
        mianji.area1(r)
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        mianji = New OverFather
        Dim width As Single = CSng(InputBox("求矩形面积，输入长"))
        Dim Height As Single = CSng(InputBox("求矩形面积，输入宽"))
        mianji.area1(width, Height)
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        mianji = New OverFather
        Dim topbottom As Single = CSng(InputBox("求梯形面积，输入上底"))
        Dim downbottom As Single = CSng(InputBox("求梯形面积，输入下底"))
        Dim Height As Single = CSng(InputBox("求矩形面积，输入高"))
        mianji.area1(topbottom, downbottom, Height)
    End Sub
End Class
Class OverFather
    Inherits FatherClass
    Overloads Sub area1(ByVal r As Single)
        MessageBox.Show("乐博网提示：圆面积为：" & r ^ 2 * 3.14)
    End Sub
    Overloads Sub area1(ByVal width As Single, ByVal height As Single)
        MessageBox.Show("乐博网提示：矩形面积为：" & width * height)
    End Sub
    Overloads Sub area1(ByVal topbottom As Single, ByVal downbottom As Single, ByVal height As Single)
        MessageBox.Show("乐博网提示：矩形面积为：" & (topbottom + downbottom) * height / 2)
    End Sub
End Class