DataBinding in ASP.NET 2.0

1. Adam Calderon – C# MVP Application Development Practice Lead InterKnowlogy DataBinding in ASP.NET 2.0

2. Agenda • ADO.NET New Features • Binding Model Changes

3. ADO.NET New Features • DbProviderFactories • SqlConnection • Web.config • SqlCommand • TransactionScope • SqlDataAdaptor • DataSet

4. ADO.NET New Features - DbProviderFactory • CreateCommand • CreateCommandBuilder • CreateConnection • CreateDataAdaptor • CreateParameter

5. ADO.NET New Features – DbProviderFactory Sample // Data Comes from Inputs on Form string provider = ProviderNameBox.Text; string connString = ConnectionStringBox.Text; string commandText = CommandTextBox.Text; // Get the provider DbProviderFactory fact = DbProviderFactories.GetFactory(provider); // Create the connection DbConnectionconn = fact.CreateConnection(); conn.ConnectionString = connString; // Create the data adapter DbDataAdapter adapter = fact.CreateDataAdapter(); adapter.SelectCommand = conn.CreateCommand(); adapter.SelectCommand.CommandText = commandText; // Run the query DataTable table = new DataTable(); adapter.Fill(table); // Shows the results Results.DataSource = table; Results.DataBind();

6. ADO.NET New Features – SqlConnection • Asynchronous Operation Support • Failover Partner • MultipleActiveResultSets (MARS) • Connection String Builders

7. ADO.NET New Features – Web.config • ConnectionStrings element ConfigurationManager.ConnectionStrings[“MySql”].ConnectionString • Protecting Connection Strings • Use aspnet_regiis.exe to encrypt web.config <protectedData> <protectedDataSections> <add name=“connectionStrings” provider=“RSAProtectedConfigurationProvider” /> </protectedDataSections> </protectedData>

8. ADO.NET New Features – SqlCommand • Async Methods • Requires Async attribute on connection string • Limited to non-query command • Reader or XmlReader • Begin/End • ExecuteNonQuery • ExecuteReader • ExecuteXmlReader • 3 Patterns for Async Implementation

9. ADO.NET New Features – SqlCommandAsync Patterns (1) // Start a non-blocking execution IAsyncResultiar = cmd.BeginExecuteReader(); // Do work while command running …. // Block the execution until done SqlDataReader reader = cmd.EndExecuteReader(iar); // Process data here WorkWithData(reader);

10. ADO.NET New Features – SqlCommandAsync Patterns (2) // Start a non-blocking execution IAsyncResultiar = cmd.BeginExecuteReader(); do { // Do work while command running …. } while (!iar.IsComleted); // Sync up and process data SqlDataReader reader = cmd.EndExecuteReader(iar); // Process data here WorkWithData(reader);

11. ADO.NET New Features – SqlCommandAsync Patterns (3) // Start a non-blocking execution IAsyncResultiar = cmd.BeginExecuteReader( new AsyncCallback(WorkWithData),cmd); // … later in your code Public void WorkWithData(IAsyncResultar) { // Retrieve the context of the call SqlCommandcmd = (SqlCommand) ar.AsyncState; // Complete the async operation SqlDataReader reader = cmd.EndExecuteReader(ar); }

12. ADO.NET New Features – TransactionScope • Supports Dispose Pattern • Determines if local or distributed transaction are needed • Objects that support ITransaction can participate

13. ADO.NET New Features – TransactionScope using (TransactionScopets = new System.Transactions.TransactionScope()) { bool success = true; using (SqlConnectionconn = new SqlConnection(ConnString)) { SqlCommandcmd = new SqlCommand(UpdateCmd, conn); cmd.Connection.Open(); try { cmd.ExecuteNonQuery(); } catch (SqlException ex) { // Error handling code goes here lblMessage.Text = ex.Message; success = false; } } // Must call to complete; otherwise abort if(success) ts.Complete(); }

14. ADO.NET New Features - SqlDataAdaptor • New Properties • AcceptChangesDuringUpdate • FillLoadOption • OverwriteChanges (Current and Orginal) • PreserveChanges (Original Only) • Upsert (Current Version of row) • ReturnProviderSpecificTypes • UpdateBatchSize

15. ADO.NET New Features - DataSet • New Properties • RemotingFormat • Binary or Xml • SchemaSerializationMode (IncludeShema/ExcludeSchema) • New Methods • CreateDataReader – Creates a reader off a Data Table

16. ADO.NET New Features – DataSetCreateDataReader DataSet data = new DataSet(); SqlDataAdapter adapter = new SqlDataAdapter( "SELECT * FROM employees;SELECT * FROM customers", ConfigurationManager.ConnectionStrings["LocalNWind"].ConnectionString); adapter.Fill(data); // Access the whole data set record by record DataTableReader reader = data.CreateDataReader(); do { while (reader.Read()) Response.Write(String.Format("{0} <br>", reader[1])); Response.Write("<hr>"); } while (reader.NextResult()); reader.Close();

17. ADO.NET New Features

18. Binding Model Changes • New Data Source Properties • Binding Expressions • Data Source Controls

19. Binding Model Changes – New Data Source Properties • DataSourceID • AppendDataBoundItems

20. Binding Model Changes – Binding Expressions (1) • DataBinder.Eval • Can be used anywhere • Eval (shortcut for DataBinder.Eval) • Can be used in the context of a data bound control • <%# Eval(“lastName”)%>

21. Binding Model Changes – Binding Expressions (2) • XPathBinder.Eval • Used with Xml data anywhere • Xpath (shortcut for XPathBinder.Eval) • Can be used in the context of a data bound control • <%# Xpath(“Orders/Order/Customer/LastName”)%> • XPathBinder.Select • Returns a nodeset that can be assigned to bound controls Data Source • DataSource=‘<%# XPathSelect(“orders/order/summary”)%>

22. Binding Model Changes – Binding Expressions (3) • Bind Method • <asp:TextBox …. Text=‘<%# Bind(“notes”)%> • Two-Way Binding • Dynamic Expressions • Evaluated when page compiles • <%$ AppSettings:AppVersionNumber %> • <%$ Resources:Resource, helloString%> • <%$ ConnectionString:localNWind%>

23. Binding Model Changes – Data Source Controls • Tabular Data Source Controls • AccessDataSource • ObjectDataSource • SqlDataSource • Hierarchical Data Source Controls • SiteMapDataSource • XmlDataSource • DataSourceView

24. Binding Model Changes – Data Source Controls – SqlDataSource (1) • Properties for all of the actions (Delete,Insert,Update,Select) • Command • Parameters • CommandType • FilterExpression / FilterParameters (only works with DataSet set for the DataSourceMode)

25. Binding Model Changes – Data Source Controls – SqlDataSource (2) • DataSourceMode • Determines how data is returned (DataSet or DataReader) • CancelSelectOnNull • Canceled data retrieval if parameter is null

26. Binding Model Changes – Data Source Controls – SqlDataSource (3) • Command contain own set of parameters • Declarative Parameters • ControlParameter • CookieParameter • FormParameter • ProfileParameter • QueryStringParameter • SessionParameter

27. Binding Model Changes – Data Source Controls – SqlDataSource (4) • Caching Behavior • CacheDuration (seconds) • CacheExpirationPolicy (absolute,sliding) • CacheKeyDependency (expiring the key) • SqlCacheDependency (table dependent) • Created with each distinct SelectCommand, ConnectionString and SelectParameters

28. Binding Model Changes

29. Session Summary • Async Features of ADO.NET can help in some situations • ConnectionString builders • New TransactionScope simplifies transactions • Binding Expressions simplify page development • New DataSource objects simplify binding to Sql Server and Objects

30. Adam Calderon • More info on InterKnowlogy:www.InterKnowlogy.com • Contact Information E-mail: adamc@InterKnowlogy.com Phone: 760-930-0075 x274 Blog: http://blogs.InterKnowlogy.com/AdamCalderon • About Adam Calderon • Microsoft MVP – C# • Microsoft UI Server Frameworks Advisory Council • Developer / Author / Speaker / Teacher