Entity Templates - ASP.NET Dynamic Data - page 132

In data models that use inheritance, derived entity classes are represented slightly differ-
ently. Imagine a CRM (Customer Relationship Management) system that has a base class
Contact and derived classes Prospect and Customer . Even though both Prospect and
Customer entities might be stored in the same database table called Contacts, Dynamic
Data provides a separate MetaTable object for each entity class. The name of each
MetaTable matches the name of the derived class, so for the Prospect entity, the MetaTable
name and the default template name is Prospect , singular:
using (CrmEntities context = new CrmEntities())
{
var prospects = from p in context.Contacts.OfType< Prospect >()
select p;
}
Template name can also be specified explicitly by setting the UIHint attribute of the
DynamicEntity control, in which case it does not have to match the table name of the
entity class at all:
<asp:DynamicEntity runat=”server” UIHint=”Contact”/>
An explicitly specified template name is a more specific match than the table name.
Therefore, if the previous code snipped is used for the Customer entity, the Contact.ascx
entity template is used even though the Customers.ascx entity template is also available.
If a matching template cannot be found based explicitly on the specified template name
or the table name, Default is used. Because Dynamic Data projects come with a set of
default entity templates out of the box, this guarantees that a matching template exists for
any entity.
Template Mode
Similar to the control mode for field templates, template mode defines the context where
the entity template will be used. It is defined by the members of the ASP.NET
DataBoundControlMode enumeration and used by Dynamic Data to determine the suffix of
the template file name:
. ReadOnly templates are used to implement the ItemTemplate of the FormView and
ListView controls. Read-only entity templates have no mode-based suffix in their
file names.
. Edit templates are used to implement the EditItemTemplate of the FormView and
ListView controls. Edit templates have _Edit at the end of their file names, such as
Default_Edit.ascx .
. Insert templates are used to implement InsertItemTemplate of the FormView and
ListView controls and have _Insert at the end of their file names, such as
Default_Insert.ascx .