Gridview checkbox not updating

Question

Hello there

I am new to programming

i am trying to update my checkbox column in a gridview which i cont

I can able to get the data 1 or 0 in database and able to update the checkbox as checked or unchecked

my code is

<asp:TemplateField HeaderText="Available" SortExpression="Available">
                <EditItemTemplate>
                    <asp:CheckBox Id="chkSelect" Checked='<%# ConvertToBool(Eval("Available")) %>' Runat="Server" />
                     </EditItemTemplate>
                <ItemTemplate>
                    <asp:CheckBox Id="chkSelect" Checked='<%# ConvertToBool(Eval("Available")) %>' Runat="Server" />
                    </ItemTemplate>
            </asp:TemplateField>

 

please help in this bug i am scratching my head for last 3 days

thanks in advance

venky