Update error after GridView editing

Question

Hi all,
I have created a Grid View and it worked fine. Then I replaced one of the text boxes in Grid View using Template Fields. Now the data is being displayed well. Even when I press the EDIT link everything sounds good. But when press UPDATE link the following
error occurs:
Cannot insert the value NULL into column 'type', table 'Sales.dbo.CR'; column does not allow nulls. UPDATE fails.
The statement has been terminated.
My code is as follows:
<asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False"
                            BorderColor="#35496A" BorderWidth="2px"
                            CellPadding="2" DataKeyNames="serial" DataSourceID="SqlDataSource1"
                            Height="50px" Width="500px"
                            HorizontalAlign="Center" CellSpacing="2" Font-Names="Calibri"
                            Font-Size="Small">
                            <EditRowStyle Font-Names="Calibri" Font-Size="Small" />
                            <FieldHeaderStyle BackColor="#C7D1E2" Font-Bold="True" Width="250px"
/>
                            <Fields>
                                <asp:BoundField DataField="serial" HeaderText="serial"
ReadOnly="True"
                                    SortExpression="serial" />
                                <asp:BoundField DataField="model" HeaderText="Model:"
SortExpression="model"
                                    ReadOnly="True" >
                                <ControlStyle Font-Names="Calibri" Font-Size="Small"
/>
                                </asp:BoundField>
                                <asp:TemplateField HeaderText="Cihaz tipi:" SortExpression="type">
                                    <EditItemTemplate>
                                        <asp:DropDownList ID="DropDownList1"
runat="server">
<asp:ListItem>Option1</asp:ListItem>
<asp:ListItem>Option2</asp:ListItem>
<asp:ListItem>Option3</asp:ListItem>
<asp:ListItem>Option4</asp:ListItem>
<asp:ListItem>Option5</asp:ListItem>
                                        </asp:DropDownList>
                                    </EditItemTemplate>
                                    <InsertItemTemplate>
                                        <asp:TextBox ID="TextBox3"
runat="server" Text='<%# Bind("type") %>'></asp:TextBox>
                                    </InsertItemTemplate>
                                    <ItemTemplate>
                                        <asp:Label ID="Label1"
runat="server" Text='<%# Bind("type") %>'></asp:Label>
                                    </ItemTemplate>
                                    <ControlStyle Font-Names="Calibri"
Font-Size="Small" />
                                </asp:TemplateField>
                                <asp:BoundField DataField="status" HeaderText="status:"
SortExpression="status" >
                                <ControlStyle Font-Names="Calibri" Font-Size="Small"
/>
                                </asp:BoundField>
                                <asp:TemplateField HeaderText="dlvdate:" SortExpression="dlvdate">
                                    <EditItemTemplate>
                                        <asp:Calendar ID="Calendar1"
runat="server"></asp:Calendar>
                                    </EditItemTemplate>
                                    <InsertItemTemplate>
                                        <asp:TextBox ID="TextBox2"
runat="server"
Text='<%# Bind("dlvdate", "{0:d}") %>'></asp:TextBox>
                                    </InsertItemTemplate>
                                    <ItemTemplate>
                                        <asp:Label ID="Label2"
runat="server" Text='<%# Bind("dlvdate", "{0:d}") %>'></asp:Label>
                                    </ItemTemplate>
                                    <ControlStyle Font-Names="Calibri"
Font-Size="Small" />
                                </asp:TemplateField>
                                <asp:TemplateField SortExpression="reptype">
                                    <EditItemTemplate>
                                        <asp:TextBox ID="TextBox1"
runat="server" Text='<%# Bind("reptype") %>'></asp:TextBox>
                                    </EditItemTemplate>
                                    <InsertItemTemplate>
                                        <asp:TextBox ID="TextBox3"
runat="server" Text='<%# Bind("reptype") %>'></asp:TextBox>
                                    </InsertItemTemplate>
                                    <ItemTemplate>
                                        <asp:Label ID="Label3"
runat="server" Text='<%# Bind("reptype") %>'></asp:Label>
                                    </ItemTemplate>
                                    <ControlStyle Font-Names="Calibri"
Font-Size="Small" />
                                </asp:TemplateField>
                                <asp:BoundField DataField="repserial" HeaderText="reptype"
                                    SortExpression="repserial" >
                                <ControlStyle Font-Names="Calibri" Font-Size="Small"
/>
                                <ItemStyle Wrap="False" />
                                </asp:BoundField>
                                <asp:CommandField ShowEditButton="True" ButtonType="Button"
CancelText="Cansel"
                                    DeleteText="Sil" EditText="Edit"
UpdateText="Update" >
                                <ControlStyle Font-Names="Calibri" Font-Size="Small"
/>
                                <FooterStyle Font-Names="Calibri" Font-Size="Small"
/>
                                </asp:CommandField>
                            </Fields>
                            <FooterStyle Font-Names="Calibri" Font-Size="Small" />
                            <RowStyle Font-Names="Calibri" Font-Size="Small" />
                        </asp:DetailsView>
Need your help :)

Answer 1

Hi Hrebadi,
Per my understanding, you are working with ASP.NET project. Please reopen your thread on ASP.NET forum for effective response. This forum is for discussing VCS programming issue. Move to
http://forums.asp.net/. Thank you for understanding.
Regards,
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