Asp.net - Pass Value Using ImageButton To Update Database?

I having problem when I try to pass value from ImageButton to a controlparameter, then the update command can retrieve the value from control parameter to execute update statement.

I want to pass value Status=1 when ImageButton APPROVE is clicked, else pass value Status=2 when ImageButton REJECT is clicked.

Where and how should I assign value Status? When I run my code, I receive this error : Must declare the scalar variable "@Status".

Or any recommendation to pass the value Status?

My ImageButton:

<ItemTemplate>
<asp:ImageButton runat="server" ID="APPROVE" CommandName="update"
ImageUrl="~/images/accept.png"

[Code]....