搞定一个在DataGrid中DropDownList模板列值初始化的问题

        我想有了下面两段就可以解决题目中的问题了，当然这个还没有涉及到模板列DropDownList数据绑定，但是我相信通过这个例子，再举一反三应该都可以解决的。这个方法应该算是比较简单的了吧，希望可以对不明白的朋友有所帮助。 :)
DataGrid模板列如下： <%# DataBinder.Eval(Container,"DataItem.Credit")%>

<asp:TemplateColumn>
                        <HeaderTemplate>
                            信誉
                        </HeaderTemplate>
                        <ItemTemplate>
                            <%# DataBinder.Eval(Container,"DataItem.Credit")%>
                        </ItemTemplate>
                        <EditItemTemplate>
                            <asp:DropDownList id="creditDlist" runat="server" Width="50" SelectedIndex='<%# DataBinder.Eval(Container, "DataItem.IndexCredit") %>'>
                                <asp:ListItem Value="良好">良好</asp:ListItem>
                                <asp:ListItem Value="较好">较好</asp:ListItem>
                                <asp:ListItem Value="一般">一般</asp:ListItem>
                                <asp:ListItem Value="较差">较差</asp:ListItem>
                            </asp:DropDownList>
                        </EditItemTemplate>
                    </asp:TemplateColumn>

SQL 语句如下：
select ID,Supp_Custom_NO,Name,rtrim(Phone) as Phone,rtrim(Fax) as Fax,Telation,Address,Zip,
      case
        when Credit='A' then '良好'
        when Credit='B' then '较好'
        when Credit='C' then '一般'
        when Credit='D' then '较差'
   end  as Credit,
     case
        when Credit='A' then 0
        when Credit='B' then 1
        when Credit='C' then 2
        when Credit='D' then 3
   end  as IndexCredit
   from Supp_Custom_TB order by Supp_Custom_NO