Problem using PayPal

I
am needing to have a button to subscribe thru PayPal.com. Below is my
.vb pagebehind. Currently it only refreshes the page without going to
PayPal. Can anyone tell what is wrong with this code?
Thank you 



        Protected Sub Subscription_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Subscription.Click

            Response.Write(PayPalPostform0().ToString)

            End Sub

        Public Function PayPalPostform0() As String

            Dim PostUrl As String = "https://www.paypal.com/cgi-bin/webscr"

 &nb ...