C＃中的下拉列表不包含列

Question

i have attatched a database to ac# application. i have three tables: movie (mid,title,director,year) reviewed(mid,rid,ratingDate, stars) and reviewer( rid, name). i want the drop down list to show only the year of the ratingDate that are in the column ( avoid null years). i then want the selected value to be sent to a grid view to display the movie title and avg rating in order of highest rating in the selected review year. everytime i run it it says system.data.dataRowView does not contain ratingDate.

here is what i have coded:

--data source for drop down list

<asp:SqlDataSource ID="yearsreviewed" runat="server" 
   ConnectionString="<%$ ConnectionStrings:ConnectionString %>" 
   SelectCommand="SELECT DISTINCT Year(ratingDate) FROM rating">
</asp:SqlDataSource>

--dropdownlist

<asp:DropDownList ID="ddlYear" runat="server" 
   DataSourceID="yearsreviewed" DataTextField="ratingDate" 
   DataValueField="ratingDate" AutoPostBack="True">
</asp:DropDownList>

--datasource for gridview

<asp:SqlDataSource ID="bestmovie" runat="server" ConnectionString="<%$       ConnectionStrings:ConnectionString %>" 
   SelectCommand="SELECT movie.title, AVG(rating.stars) AS newRating, rating.ratingDate FROM movie INNER JOIN rating ON movie.mid = rating.mid WHERE (rating.ratingDate IS NOT NULL) AND (YEAR(rating.ratingDate) = @ratingDate) GROUP BY rating.ratingDate, movie.title ORDER BY rating.ratingDate, newRating DESC">
   <SelectParameters>
      <asp:ControlParameter ControlID="ddlYear" Name="ratingDate" PropertyName="SelectedValue" />
   </SelectParameters>
</asp:SqlDataSource>`

--gridView

<asp:GridView ID="gvBestMovie" runat="server" AutoGenerateColumns="False" 
   CellPadding="4" DataSourceID="bestmovie" ForeColor="#333333" 
   GridLines="None">
   <AlternatingRowStyle BackColor="White" />
      <Columns>
         <asp:BoundField DataField="title" HeaderText="title" SortExpression="title" />
         <asp:BoundField DataField="newRating" HeaderText="newRating" ReadOnly="True" 
                SortExpression="newRating" />
         <asp:BoundField DataField="ratingDate" HeaderText="ratingDate" 
                SortExpression="ratingDate" />
      </Columns>
      <EditRowStyle BackColor="#7C6F57" />
      <FooterStyle BackColor="#1C5E55" Font-Bold="True" ForeColor="White" />
      <HeaderStyle BackColor="#1C5E55" Font-Bold="True" ForeColor="White" />
      <PagerStyle BackColor="#666666" ForeColor="White" HorizontalAlign="Center" />
      <RowStyle BackColor="#E3EAEB" />
      <SelectedRowStyle BackColor="#C5BBAF" Font-Bold="True" ForeColor="#333333" />
      <SortedAscendingCellStyle BackColor="#F8FAFA" />
      <SortedAscendingHeaderStyle BackColor="#246B61" />
      <SortedDescendingCellStyle BackColor="#D4DFE1" />
      <SortedDescendingHeaderStyle BackColor="#15524A" />
</asp:GridView>

i have done almost the exact same thing with a different query and it works great. please help i dont know what im missing

Answer 1

在yearsreviewed数据源中，您是否尝试过在select语句中使用别名？

SELECT DISTINCT Year(ratingDate) as ratingDate FROM rating