vb.net - Page shouldnt load after an event execution in asp.net -

in aspx page on clicking button in displaying popuop(making visible true div). in popup have few controls have events handled.

these events handling methods have been written on server side code(xyz.aspx.vb).

the problem after these event handled page lifecycle executed again.due popups div tag visibility becomes false , popup not displayed.

how can execute event handling method , not loading page @ server side.

ah yes, 1 of caveats of server side controls, e.g <asp:button runat="server"> fire postback (i.e page reload).

i believe cannot stopped, unless add event.preventdefault(); script control, nullifies purpose of having code-behind event in first place.

what i'd suggest if don't want go through having reload page when click server side control, using ajax posts server won't fire page reload.