我有兩個搜索下拉列表,第一個列表是針對城市,第二個列表是針對所選城市的區域。我希望在第二個下拉列表中添加一個默認值,默認情況下會搜索所有區域,除非從包含特定搜索的區域ID的列表中選擇特定區域。asp.net dropdownlist
<asp:DropDownList ID="DropDownList1" runat="server"
DataSourceID="SqlDataSource1" DataTextField="cityName" AutoPostBack="true" DataValueField="cityID">
</asp:DropDownList>
<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:ConnectionString %>"
SelectCommand="SELECT * FROM [Cities]"></asp:SqlDataSource>
<asp:DropDownList ID="DropArea" runat="server" DataSourceID="SqlArea"
DataTextField="areaName" DataValueField="areaID">
</asp:DropDownList>
<asp:SqlDataSource ID="SqlArea" runat="server"
ConnectionString="<%$ ConnectionStrings:ConnectionString %>"
SelectCommand="SELECT * FROM [area] WHERE ([cityID] = @cityID)">
<SelectParameters>
<asp:ControlParameter ControlID="DropDownList1" DefaultValue="0" Name="cityID"
PropertyName="SelectedValue" Type="Int16" />
</SelectParameters>
</asp:SqlDataSource>
<asp:Button ID="Button1" runat="server" Text="Search" onclick="Button1_Click" />
這裏有問題嗎? – James 2010-12-10 23:34:46
我想在第二個下拉列表中添加一個默認值,該默認值將默認搜索所有區域 – Chris 2010-12-10 23:37:38