Databases Reference
In-Depth Information
The
GetChildrenPath
methods of the
MetaChildrenColumn
class are used when a hyper-
link is needed to navigate from a parent entity to its children. They retrieve the primary
key values from the specified
row
and pass them to the
GetActionPath
method of the
ChildTable
. The generated URL contains the route to the child table, including name of
the page template based on the specified
action
and primary key names and values in
the query. This is how the Children field template generates a hyperlink that takes the
user from the parent entity to the List page of the child entity, filtered by the parent's
primary key.
Dynamic Data metadata API provides the information web applications need to generate
pages dynamically. The
MetaModel
class serves as the entry point for registering data
models and accessing the metadata. The
MetaTable
class describes a single entity as a
collection of attributes, such as
DisplayName
and
SortColumn
and a collection of
MetaColumn
objects that describe the entity properties. The
MetaColumn
class describes
primitive entity properties and has two descendant classes—
MetaForeignKeyColumn
, which
describes many-to-one and one-to-one navigation properties, and
MetaChildrenColumn
,
which describes one-to-many and many-to-many navigation properties.
The metadata API in Dynamic Data relies on metadata providers, which are special classes
designed to extract metadata information from the underlying data access framework and
present it to the meta model classes in a uniform format. Dynamic Data ships with built-
in providers for Entity Framework and LINQ to SQL and allows creating custom providers
for other data access frameworks.
