Question

Please cosider this scenario:

I have a form with 3 drop down list.I place these controls in an update panel.when my users select an Item with value greater that 2 in first drop down list I disable second and third drop down list with jQuery. My problem is after any post back all drop down list are enable.I know this is normal but how I can check the form again and disable controls that should be disable?

thanks

Edit 1)

this is my code:

<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
        <ContentTemplate>
            <table border="1" cellpadding="0" cellspacing="0">
                <tr>
                    <td>
                        <asp:DropDownList ID="DropDownList1" runat="server" Width="100px">
                            <asp:ListItem Value="1" Text="1" />
                            <asp:ListItem Value="2" Text="2" />
                            <asp:ListItem Value="3" Text="3" />
                        </asp:DropDownList>
                    </td>
                </tr>
                <tr>
                    <td>
                        <asp:DropDownList ID="DropDownList2" runat="server" Width="100px">
                            <asp:ListItem Value="1" Text="1" />
                            <asp:ListItem Value="2" Text="2" />
                            <asp:ListItem Value="3" Text="3" />
                        </asp:DropDownList>
                    </td>
                </tr>
                <tr>
                    <td>
                        <asp:DropDownList ID="DropDownList3" runat="server" Width="100px">
                            <asp:ListItem Value="1" Text="1" />
                            <asp:ListItem Value="2" Text="2" />
                            <asp:ListItem Value="3" Text="3" />
                        </asp:DropDownList>
                        <br />
                    </td>
                </tr>
            </table>
            <div>
                <asp:Button ID="Button1" runat="server" Text="Cause Post Back" Width="200px" 
                    onclick="Button1_Click"/>
            </div>
        </ContentTemplate>
    </asp:UpdatePanel>

and javascript:

 $(document).ready(function () {
        function Disable(item) {
            item.attr('disabled', 'disabled');
        }
        $('#DropDownList1').change(function () {
            if ($(this).val() > 2) {
                Disable($('#DropDownList2'));
                Disable($('#DropDownList3'));
            }
            else {
                Enable($('#DropDownList2'));
                Enable($('#DropDownList3'));
            }
        }).change();

        function Enable(item) {
            item.removeAttr('disabled');
        }
    });

Answer 1

Am I missing something?

$('#dropdown1').change(function()
{
    if ( $(this).val() > 2 )
    {
        $('#dropdown2, #dropdown3').prop('disabled', true);
    }
    else
    {
        $('#dropdown2, #dropdown3').prop('disabled', false);
    }
})
.change();