Dynamic data. Table selection from DropDownList for scaffold in GridView

Question

I have been struggling with this ASP.NET dynamic data problem for several days ... I have a DropDownList containing the table names of all the tables in my data context (.dbml). When I select DropDownList, it should tint the selected table in the GridView. My code works 100% in the MetaTable subclass of GridView (it implements all the rules that I applied in my metaclasses).

However, filtering seems to work if I explicitly add DynamicExpression to the QueryExtender declaration:

<asp:QueryExtender ID="GridQueryExtender" TargetControlID="GridDataSource" runat="server"> <asp:DynamicFilterExpression ControlID="FilterRepeater" /> </asp:QueryExtender> 

This, in turn, requires me to explicitly specify MetaTable in LinqDataSource (linqdsData), either programmatically in Page_Load syntax or in ASP.NET syntax.

Since the GridView gets the forests in the Page_Load part of the life cycle, this approach does not work for me, since it takes place in the Page_Init part of the life cycle.

So my requirement is that as soon as I select another table to populate the GridView with DropDownList, the FilterRepeater should reflect the filters of the just selected MetaTable.

Do I have any way to programmatically update FilterRepeater in Page_Load so that it contains the MetaTable filters that I selected in DropDownList.

Below is the code of my code:

ASP.NET Page Code:

  protected void Page_Load(object sender, EventArgs e) { if (ddlTable.SelectedIndex > 0) { string tableName = ddlDataType.SelectedValue; linqdsData.TableName = tableName; MetaTable mt = ASP.global_asax.DefaultModel.GetTable(tableName); GridViewData.SetMetaTable(mt, mt.GetColumnValuesFromRoute(Context)); GridViewData.EnableDynamicData(mt.EntityType); GridViewData.DataSourceID = linqdsData.ID; } } 

ASP.NET Page:

 <asp:Panel runat="server" ID="pnlFilters" CssClass="gridFilterCon" EnableTheming="True"> <div class="filterGridHeading"> Filter the grid by:</div> <asp:QueryableFilterRepeater runat="server" ID="FilterRepeater"> <ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Eval("DisplayName") %>' OnPreRender="Label_PreRender" CssClass="gridFilterLbl" /> <asp:DynamicFilter runat="server" ID="DynamicFilter" /> <br /> </ItemTemplate> </asp:QueryableFilterRepeater> <asp:Button ID="btnFilter" runat="server" Text="OK" EnableTheming="False" UseSubmitBehavior="False" OnClick="btnFilter_Click" /> </asp:Panel> <asp:GridView ID="GridViewData" runat="server" OnSelectedIndexChanged="GridViewData_SelectedIndexChanged" OnPreRender="GridViewData_PreRender" OnRowDataBound="GridViewData_RowDataBound" OnPageIndexChanged="GridViewData_PageIndexChanged" AllowPaging="True" PageSize="50" OnInit="GridViewData_Init"> <Columns> ... </Columns> <PagerTemplate> <asp:GridViewPager ID="GridViewPager1" runat="server" /> </PagerTemplate> <PagerSettings Mode="NumericFirstLast" NextPageText="Next" /> </asp:GridView> <asp:LinqDataSource ID="linqdsData" runat="server" ContextTypeName="pdcDataContext" OnSelected="linqdsData_Selected" OnSelecting="linqdsData_Selecting" EnableUpdate="True"> </asp:LinqDataSource> <asp:QueryExtender ID="GridQueryExtender" TargetControlID="linqdsData" runat="server"> </asp:QueryExtender> 

Your help will be greatly appreciated.

Answer 1

It looks like you are trying to do a lot on one web page. This creates complexity for the type you are experiencing: for each table, different filters and meta tags are required. Trying to keep each element straight, requires a bunch of radio buttons and / or if ... then statements. I recommend an alternative approach. Instead of doing all this on one page:

• Create a web page for each table
• Configure appropriate filters and meta tags
• Copy the DropDownList containing the table names of all tables to each web page, and use it to redirect to the corresponding web page.

ASP.net dynamic data makes it easy to create web pages for each table. This is what scaffolding is. Using the above approach, each web page will process its own set of problems that are targeted to a specific table.

Hope this helps.