在查询中使用 DropDownList 中的选定项目

Question

我正在尝试使用 SELECT 查询中下拉列表中的选定项目。这是我的代码：

<asp:SqlDataSource ID="SqlDataSource3" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT tblAirport.Name, tblFlight.Destination, tblFlight.FlightDate FROM tblAirport INNER JOIN tblFlight ON tblAirport.AirportCode = tblFlight.AirportCode WHERE Destination = DropDownList1.SelectedItem.Value"></asp:SqlDataSource>

但是，从这段代码中，我在选择项目时遇到错误：

“DropDownList1.SelectedItem.Value”无法绑定。

有人有什么建议吗？

Answer 1

你可以这样做：

<asp:SqlDataSource ID="SqlDataSource3" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT tblAirport.Name, tblFlight.Destination, tblFlight.FlightDate FROM tblAirport INNER JOIN tblFlight ON tblAirport.AirportCode = tblFlight.AirportCode WHERE (Destination = @Destination)"> <SelectParameters> <asp:ControlParameter ControlID="DropDownList1" Name="Destination" PropertyName="SelectedValue" /> </SelectParameters> </asp:SqlDataSource>