asp.net - 在 SqlDataSource 的 SelectCommand 中使用下拉列表的选定值

Question

我想在 SqlDataSource SelectCommand 中使用下拉列表的选定值。

                <asp:DropDownList ID="ddlSelectRole" runat="server" ClientIDMode="Static">
                    <asp:ListItem></asp:ListItem>
                    <asp:ListItem>Client</asp:ListItem>
                    <asp:ListItem>Programming</asp:ListItem>
                    <asp:ListItem>Guest</asp:ListItem>
                </asp:DropDownList>

当前:

<asp:SqlDataSource ID="dsourceProgEmails" runat="server" 
    ConnectionString="<%$ ConnectionStrings:ProjectConnectionString %>" 
    SelectCommand="SELECT  [Email] + ',' AS [text()] FROM [SiteUsers] WHERE [Role] = 'Programming' FOR XML PATH ('')">
</asp:SqlDataSource>

我在想这样的事情:

<asp:SqlDataSource ID="dsourceProgEmails" runat="server" 
    ConnectionString="<%$ ConnectionStrings:ProjectConnectionString %>" 
    SelectCommand="SELECT  [Email] + ',' AS [text()] FROM [SiteUsers] WHERE [Role] = '" + ddlSelectRole.SelectedValue + "' FOR XML PATH ('')">
</asp:SqlDataSource>

后台代码是 C#。

Answer 1

您的查询在 SqlDataSource 中应如下所示:

SelectCommand="SELECT [Email] + ',' AS [text] FROM [SiteUsers] WHERE [Role] = @RoleID FOR "

然后在此处指定从何处获取 RoleID 的值

<SelectParameters>
   <asp:ControlParameter Name="RoleID" ControlID="ddlSelectRole" 
        PropertyName="SelectedValue" />
</SelectParameters>

• ControlParameter Class - Used with SqlDataSource
• ControlParameter example: how to use ControlParameter