The Hyperlink control does not have a server side click event but you could use a link button like this:
<asp:LinkButton id="LinkButton1" runat="server">Continue</asp:LinkButton>
then in your code behind
Private Sub LinkButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles LinkButton1.Click
'run your code here
'then
Server.Transfer("NextPage.aspx")
End Sub
Simon