Dropdown list issue

I have a page im trying to get to work, and it wont for some unknown reason. i am hoping one of you could lend me a hand.


i have a  dropdownlist and i want, if one certain item is selected for the webpage to change.
It however does nothing but just postback, nothing changes,


here is my code
aspx first

<body>
    <form id="form1" runat="server">
    <div>
    
    </div>
    <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True"
        DataSourceID="SqlDataSource1" DataTextField="Location"
        DataValueField="Location"
        onselectedindexchanged="DropDownLi ...