Pass Parameter in PostBackUrl on LinkButton Click in ASP.Net

​Hi

In href i want that value "A" should be passed means that user wants to Update record.

In this how i can pass value "A" on PostBackUrl.

<div class="list-icons">
    <asp:LinkButton ID="lnkbtnAdd" runat="server" PostBackUrl="~/Admin/ActionType" class="btn bg-info btn-sm ml-3"><i class="icon-plus3 mr-2"></i>Add</asp:LinkButton>
</div>

Thanks