Button Calling a Sub to then open a new window

[andyfreeman]

hello all

On my page currently when i click the button it loads the page in
existing window.

Paf_Id is a variable declared in the page, i pass this through to the
new page whenever i click the button

Current Function:
sub next_page(s As Object, e As EventArgs)
response.Redirect("datagrid2.aspx?paf_id=" & paf_id)
end sub

Current Button:
<asp:button ID="btn_next" CssClass="event_button"
CausesValidation="false" Text="Show Main Update Grid"
OnClick="next_page" runat="server" />

When i would ike to happen when i click the button is it loads the page
up in a new window(will change size of window later, but just want to
get new window 1st)

I have had a search around and i have seen other people have got
solutions, but being very new to this am struggling to apply this to my
page.

if anyone could help me i would really appreciate it as av been banging
my head against the wall for a few hours now

Thanks in advance