Asp.net 更新 DropDownList 选定项

Question

I'm stuck into a problem using a DropDownList item into a form. The main form is feed by an SQLDataSource ... all form widget are bound to a specific record field etc. I changed one of the form widget (a TextBox) with a DropDownList to allow the user to only select between a number of values... I feed this control trough another SQLDataSource. While the form is in Insert mode there are no problems but when I switch into Edit mode I'm not able to set the DropDownList selected item with the value coming from the main record. Ho can I fix this? Here's a sample of my .aspx code:

<asp:FormView ID="_frmData" runat="server" DataKeyNames="id" DataSourceID="_sdsTable1" DefaultMode="Insert">
    <InsertItemTemplate>
        <asp:TextBox ID="_txtField0" runat="server" Text='<%#Bind("field0")%>'/>
        <asp:DropDownList ID="_ddlField1" runat="server" DataSourceID="_sdsTable2" DataTextField="field_text" DataValueField="field_value" AppendDataBoundItems="true">
            <asp:ListItem Value="" Text="None" Selected="True" />
     </asp:DropDownList>
</InsertItemTemplate>
<EditItemTemplate>
     <asp:TextBox ID="_txtField0" runat="server" Text='<%#Bind("field0")%>'/>
     <asp:DropDownList ID="_ddlField1" CssClass="input_medium" runat="server" DataSourceID="_sdsTable2" DataTextField="field_text" DataValueField="field_value" AppendDataBoundItems="true">
           <asp:ListItem Value="" Text="None" Selected="True" />
     </asp:DropDownList>
</EditItemTemplate>
</asp:FormView>
<asp:SqlDataSource ID="_sdsTable1" runat="server" ConnectionString="<%$ ConnectionStrings:_db %>"
                    ProviderName="<%$ ConnectionStrings:_db.ProviderName %>"
                    SelectCommand=" SELECT
                                        field0, field1
                                    FROM
                                        table1
                                    WHERE
                                        id=@id;"
                    UpdateCommand=" UPDATE
                                        table1
                                    SET
                                       `field0` = @field0
                                       `field1` = @field1
                                    WHERE
                                        id = @id;""
                    InsertCommandType="StoredProcedure"
                    InsertCommand="create_table1_entry">
<InsertParameters>
    <asp:ControlParameter Name="field1" ControlID="_frmData$_ddlField1" Type="String" PropertyName="SelectedItem.Text" />
</InsertParameters>
<UpdateParameters>
    <asp:ControlParameter Name="field1" ControlID="_frmData$_ddlField1" Type="String" PropertyName="SelectedItem.Text" />
</UpdateParameters>
</asp:SqlDataSource>

<asp:SqlDataSource ID="_sdsTable2" runat="server" ConnectionString="<%$ ConnectionStrings:_db %>"
                    ProviderName="<%$ ConnectionStrings:_db.ProviderName %>"
                    SelectCommand=" SELECT
                                        field_value, field_text
                                    FROM
                                        table2;" />

Answer 1

Try This

myDropDown.Items.FindByValue("Your Main Record Value").Selected=true;

OR

myDropDown.Items.FindByText("Your Main Record Text").Selected=true;

Answer 2

I CAN JUST use SelectedValue='<%#Bind("field1")%>' property in DDL to achieve the result, just as I was guessing. The only issue here is the why Intellisense is not suggesting SelectedValue as a propery for DropDownList ... thnx everyone.