Chapter 1. Secrets of Real World ASP.NET Dynamic Data Web Sites

Dynamic Data is a set of data features in ASP.NET that use metadata of an entity field to determine what set of user interface (UI) controls to render to the user. The easiest-to-envision example of this behavior is what is known as scaffolding. A Dynamic Data web site can create a full set of create, read, update, and delete (CRUD) screens automatically by looking at the database table metadata. These screens feature UI controls appropriate for the different database types — all without writing code. While the scaffolding often gets the most attention, there is a host of additional power and flexibility available from the Dynamic Data features.

To illustrate, consider a URL field in a database table. With no special customizations when viewing the URL field, Dynamic Data knows to use controls and logic appropriate to render a string type to the user. While the URL field may be a string, semantically the data is a location on the Web. When users are dealing with URLs, a better experience is built by allowing them to click on a link and use the URL as something more than a string. By assigning extra metadata to the URL field, the web site can respond with UI controls more appropriate for the data. Therefore, whether the system uses the native data type or custom metadata, Dynamic Data sites build the user interface either based on what the data is or what the data means.