C# 4 and .NET 4

1258 ❘ ChaPTer 42 Asp.net dynAmic dAtA And mvc
Configuring routing
One of the most important concepts to grasp when dealing with dynamic data sites is that pages are
generated according to actions. An action is a way of defining what a page should do in response to, for
example, the user clicking on a particular link. There are four page actions that are defined for you by
default: List, Details, Edit, and Insert.
Each of the page templates defined for a dynamic data site (which are also known as views) can function
differently according to what action is currently being performed. The routing configuration for the web
site associates actions with views, and each route can optionally be constrained by the tables that it should
apply to. For example, you might create a new view that is intended for listing customers. That view might
function differently from the default List.aspx view. To create the new view, you must configure routing
so that the correct view will be used.
The default routing for a dynamic data web site is configured in Global.asax as follows:
routes.Add(new DynamicDataRoute("{table}/{action}.aspx")
{
Constraints = new RouteValueDictionary(
new { action = "List|Details|Edit|Insert" }),
Model = DefaultModel
});
code snippet PCSDynamicDataDemoEntities/Global.asax and PCSDynamicDataDemoLinq/Global.asax
This uses the routing framework described earlier in the chapter, although here routes use the
DynamicDataRoute type. This class derives from Route and provides specialized functionality for dealing
with actions, views, and tables.
You will notice in this code that this route includes the name of a table and the name of an action — where
the value of the action is constrained to the four predefined page action types. To take the example of using
a different view for listing customers, you might add the following route (before the existing one, or that one
would take precedence):
routes.Add(new DynamicDataRoute("Customers/List.aspx")
{
Table = "Customers",
Action = PageAction.List,
ViewName = "ListCustomers",
Model = DefaultModel
});
This route associates the /Customers/List.aspx URL with the view ListCustomers.aspx, and so for
this code to work, you must supply a file of this name in the PageTemplates directory. You can also see that
the Table and Action properties are specified here, as they are not available in the URL any more. The way
the dynamic data routing works is that {table} and {action} routing parameters are used to populate the
Table and Action properties, and in this URL these parameters are not present.
You can build up as complex a system of routing as you wish in this manner, providing specialized pages for
tables and actions as you see fit. You can also make use of the ListDetails.aspx view, which is a masterdetail
view of data that enables row selection and inline editing. To use this view, you can supply alternative
routes, or simply uncomment the following routes that the dynamic data site template provides:
//routes.Add(new DynamicDataRoute("{table}/ListDetails.aspx")
//{
// Action = PageAction.List,
// ViewName = "ListDetails",
// Model = DefaultModel
//});
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