Creating a New Dynamic Data Web Site Using Scaffolding (LINQ toSQL And Using Website)

This Post is to show you   how to create a basic Web site that uses ASP.NET Dynamic Data. Dynamic Data enables you to create a data-driven Web site with little or no coding.

An important feature of Dynamic Data is the scaffolding framework. When scaffolding is enabled in a Dynamic Data Web site, ASP.NET analyzes the application's data model and generates Web pages dynamically based on the data in the data model. These auto-generated Web pages provide the capability to display, insert, delete, and edit data for each table.

Creating a Dynamic Data Web Site

1.     Start Visual Studio or Visual Web Developer.

2.     In the File menu, click NewWeb Site.

3.     The New Web Site dialog box is displayed.

4.     Under Installed Templates, in the left pane, select Visual Basic or Visual C#.

5.     In the centre pane, select one of the following:

• To use the LINQ to SQL model, select ASP.NET Dynamic Data LINQ to SQL Web Site

6.  In the Web Location box, select File System and then enter the name of the folder where you want to keep the

      pages of the Web site.For example, enter the folder name C:\WebSites\DynamicData.

 7.  Click OK.

Visual Studio creates the Web site.

Adding Data to the Web Site

The next step is to add a database to the project. Later you will use the database to create a data context (classes to represent database entities) and then register the data context for use by Dynamic Data.

To add the database file to the project

1.       In Solution Explorer, right-click the App_Data folder and then click Add Existing Item.

The Add Existing Item dialog box is displayed.

2.       Enter the location where you installed the AdventureWorksLT database file (AdventureWorksLT_Data.mdf).

Note

This procedure will create a copy of the database file in the project. If it is impractical to  make a copy of the database, you can connect to it by using an alternative method, such as  attaching the database file directly. However, the procedure for doing this is not covered in  this Post.

The next step is to create the data model. The procedure differs slightly depending on whether you want to use LINQ to SQL or the ADO.NET Entity Framework to create the data model. Use the procedure that applies to the data model that you want to create.

To create the data model using LINQ to SQL

1.       If you are using a Web site project and the Web site does not already have an App_Code folder, in Solution Explorer, right-click the project, click Add ASP.NET Folder, and then click App_Code. Right-click the App_Code folder and then click Add New Item.

2.       If you are using a Web application project, in Solution Explorer, right-click the project, click Add, and thenclick New Item.

3.       Under Installed Templates, in the left pane, perform one of the following:

o    If you are using a Web site project, select Visual Basic or Visual C#.

o    If you are using a Web application project, expand the Visual Basic or Visual C# menu and then select Data.

4.       In the center pane, click LINQ to SQL Classes.

5.       In the Name box, enter a name for the database model.

For example, enter the name AdventureWorksLT.dbml.

6.       Click Add.

The Object Relational Designer is displayed.

7.       In the O/R Designer, click the Server Explorer link (Database Explorer in Visual Web Developer).

8.       In Server Explorer (Database Explorer), under Data Connections, expand the database file node and then expand the Tables node.

Note

If the database file node does not exist, in Solution Explorer, double-click the database file.  This will create a connection to the database and the file node will be displayed in  Server Explorer.

9.       Drag all the tables into the O/R Designer.

Each table is represented as an entity that is named for the corresponding database table.

10.    Save the AdventureWorksLT.dbml file.

11.    In Solution Explorer, open the AdventureWorksLT.designer.cs or AdventureWorksLT.designer.vb file that is located under the .dbml file node.

Notice that the .dbml file contains the AdventureWorksLTDataContext class that represents the database. It also contains entity classes, such as the Productand Employee classes, that represent database tables. The constructor for the AdventureWorksLTDataContext class reads the connection string from the Web.config file.

12.    Open the Web.config file.

Notice that the connectionStrings element contains the connection string to the AdventureWorksLT database.

13.    Close the class file and the Web.config file.

To register the data context

1. Open the Global.asax file.
2. Uncomment the line that contains the DefaultModel.RegisterContext method.Set the appropriate context type and the variable ScaffoldAllTables to true.For  the LINQ-to-SQL model, use the following code:

C#

DefaultModel.RegisterContext(typeof(AdventureWorksLTDataContext), 
    new ContextConfiguration() { ScaffoldAllTables = true });

Security Note

Enabling scaffolding (setting the variable ScaffoldAllTables to true) can pose a security risk because you are exposing all  the tables in the data model for display and edit operations.

Testing the Dynamic Data Web Site

You can now test the Dynamic Data Web site that you just created.

 To test the Web site

1.      In Solution Explorer, right-click the Default.aspx page, and then click View in Browser.

2.      The page displays a list that contains the tables that you added to the data model.

3.      Click one of the tables. For example, click the Products table.

4.      A page is displayed that contains the data from the table that you selected. For tables that contain foreign-key fields, a link is provided to the details page of the referenced table. If the table is a parent table in a one-to-many relationship, a link is provided to the list page of the child table.

5.     Click the Delete button to delete a record from the table.

6.     Click the page numbers to navigate through the records.

7.     Click the Edit button to modify a record in the table.

8.     Change the values and then click Update, or click Cancel to cancel the edit operation.

9.     At the bottom of the page, click the Insert new item button to create a new record.

10.  A page is displayed that contains data entry fields.

11. Provide the new record information and then click Insert, or click Cancel to cancel the insert operation.

12. When you have finished, close the browser.