DropDownList5' has a SelectedValue which is invalid

Question

Hi Guys

please help me

 

i use girideview when i update data the dropdownlist of City update null in the value and not display as data bind value

 

below the code  

 

<asp:TemplateField HeaderText="City" SortExpression="City">

<EditItemTemplate>

<asp:DropDownList ID="DropDownList5" runat="server" AutoPostBack="True"

DataSourceID="SqlDataSource2" DataTextField="City" DataValueField="City"

Width="90" Font-Size="Small" Font-Names="Calibri" >

<asp:ListItem>Selected City</asp:ListItem>

</asp:DropDownList>

<asp:SqlDataSource ID="SqlDataSource2" runat="server"

ConnectionString="<%$ ConnectionStrings:Cash_PlanConn %>"

SelectCommand="SELECT City FROM RegionCity2 WHERE (Region = @Region)">

<SelectParameters>

<asp:ControlParameter ControlID="DropDownList6" Name="Region"

PropertyName="SelectedValue" Type="String" />

</SelectParameters>

</asp:SqlDataSource>

<asp:RequiredFieldValidator ID="rfvEditCity" runat="server" ErrorMessage="City Is Required"

ControlToValidate="DropDownList5" Text="*Required" ForeColor="Red"></asp:RequiredFieldValidator>

</EditItemTemplate>

<ItemTemplate>

<asp:Label ID="Label14" runat="server" Text='<%# Bind("City") %>'></asp:Label>

</ItemTemplate>

<FooterTemplate>

<asp:DropDownList ID="dd_City" runat="server" AutoPostBack="True"

DataSourceID="SqlDataSource3" DataTextField="City" DataValueField="City"

Width="90" Font-Size="Small" Font-Names="Calibri">

<asp:ListItem>Selected City</asp:ListItem>

</asp:DropDownList>

<asp:SqlDataSource ID="SqlDataSource3" runat="server"

ConnectionString="<%$ ConnectionStrings:Cash_PlanConn %>"

SelectCommand="SELECT City FROM RegionCity2 WHERE (Region = @Region)">

<SelectParameters>

<asp:ControlParameter ControlID="dd_Region" Name="Region"

PropertyName="SelectedValue" Type="String" />

</SelectParameters>

</asp:SqlDataSource>

<asp:RequiredFieldValidator ValidationGroup="INSERT" ID="rfvInsertCity" runat="server" ErrorMessage="City Is Required"

ControlToValidate="dd_City" Text="*Required" ForeColor="Red"></asp:RequiredFieldValidator>

</FooterTemplate>

</asp:TemplateField>

 

ERROR :

 

 

 Grid View: