Databases Reference
In-Depth Information
LISTING 6.5
Continued
<img runat=”server” src=”~/DynamicData/Content/Images/plus.gif”/>
Insert new item
</asp:DynamicHyperLink>
</div>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>
The
GridView
control is configured to allow paging and sorting. It includes a single
TemplateField
to define a column that displays action links—Edit, Delete, and Details.
The actual data columns are generated dynamically by a
DefaultAutoFieldGenerator
.
During page initialization, the
DynamicDataManager
control sets the
ColumnsGenerator
property of the
GridView
with a new instance of the
DefaultAutoFieldGenerator
class. So,
instead of being specified explicitly in page markup, as shown in the example below, the
DynamicField
instances are created dynamically, based on the metadata information
describing properties of the current entity type.
<Columns>
<asp:DynamicField DataField=”ProductName”/>
<asp:DynamicField DataField=”UnitsInStock”/>
</Columns>
Paging functionality is implemented by the
GridViewPager
control. This is not a built-in
ASP.NET control; it is a user control included in the Dynamic Data project templates of
Visual Studio and created in the
DynamicData\Content
folder of your web application
when you first create the project.
The
QueryableFilterRepeater
control, which was discussed in Chapter 5, is used to
generate a set of
DynamicFilter
controls, one for each property that can be filtered using
filter templates available in the
DynamicData\Filters
folder of the web application. Notice
that this markup does not specify the
DataField
property of the DynamicFilter control.
This is done automatically when the
QueryableFilterRepeater
instantiates its
ItemTemplate
for each filterable property in the entity type. The
ID
property of the
DynamicFilter
control has to be
“DynamicFilter
,
”
which is what the
QueryableFilterRepeater
looks for by default.
The
QueryableFilterRepeater
control is associated with the
QueryExtender
by the
DynamicFilterExpression
in the page markup. In its turn, the
QueryExtender
control is
associated with the
EntityDataSource
, which allows the individual filter templates to
modify the LINQ query it generates at run time based on the values selected by the user.
Listing 6.6 shows the code-behind file of the List page template, again, cleaned-up to
improve readability and highlight important points.
