下面程序段运行结果是( ) Function fun(x As Integer, y As Integer) As Integer x = x + y If x <> 0 Then fun = x Else fun = y End If End Function Private Sub Command1_Click() Dim a As Integer, b As Integer a = 2: b = 3 Text1.Text = fun(a, b) Text2.Text = fun(a, b) Text3.Text = fun(a, b) End Sub