Introduction to ASP.NET Dynamic Data
ASP.NET Dynamic Data brings major usability and RAD development changes to the existing ASP.NET data controls. RAD development is significantly increased by the use of a rich scaffolding framework. After you add a LINQ to SQL or Entity Framework data model to a project, you can simply register it with Dynamic Data. The result is a fully functional Web site. Full CRUD (create, read, update, and delete) operations are supported. The site includes filtering by foreign keys and Boolean fields; foreign keys are automatically converted to their friendly names. Smart validation is automatically available, which provides validation based on database constraints for nullable fields, data type, and field length.
The DetailsView and GridView controls have been extended to display fields by using templates instead of by using hard-coded rules that are programmed in the controls. These templates are part of the project, and you can customize them to change their appearance or to specify which controls they use for rendering. This makes it very easy to make a change in one place in your site that specifies how to present dates for editing, as one example. FormView and ListView controls can implement similar behavior by using a DynamicControl object in their templates and by specifying which field in the row to display. Dynamic Data will then automatically build the UI for these controls based on the templates that you specify.
Validation is significantly improved in the controls as well. The controls read metadata for a LINQ to SQL or Entity Framework data model and provide automatic validation based on the model. For example, if a column in the database is limited to 50 characters, and if a column is marked as not nullable, a RequiredFieldValidator control is automatically enabled for the column. (The controls also automatically support data-model-level validation.) You can apply other metadata to take further control over display and validation.
We have received many reports from people usng the RTM release of Dynamic Data encountering some errors when using it with Entity Framework. This problem occurs with certain types of data relationships and typically generates an error that looks similar to: "A property with name 'XX.Id' does not exist in metadata for entity type 'XX.XX.XXXX'. An update to .NET 3.5 SP1 has been released that corrects these issues, please see KB959209 which contains the update. Here is a direct link to the knowledge base article: http://support.microsoft.com/kb/959209
