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dropdownlist null value

Posted By:      Posted Date: August 29, 2010    Points: 0   Category :ASP.Net
i am using detailview control for my data entry form in edit templet i am using dropdownlist for selecting countries this is my binding code:<EditItemTemplate>                    <asp:DropDownList ID="DropDownListCountryET" runat="server"                         DataSourceID="SqlDataSourceCountries" DataTextField="CountryName"                         DataValueField="ID" SelectedValue='<%# bind("FK_Countries_ID") %>' >                                          </asp:DropDownList>                    <asp:RequiredFieldValidator ID="RequiredFieldValidator4" ControlToValidate="DropDownListCountryET" Text="Please select Country" Runat="Server" />                </EditItemTemplate><EditItemTemplate>                    <asp:DropDownList ID="DropDownListCountryET" runat="server"   

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