DataBinding in ASP.NET 2.0
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Transcript of DataBinding in ASP.NET 2.0
DataBinding in ASP.NET 2.0
Adam Calderon – C# MVPApplication Development Practice LeadInterKnowlogy
Agenda
ADO.NET New Features Binding Model Changes
ADO.NET New Features
DbProviderFactories SqlConnection Web.config SqlCommand TransactionScope SqlDataAdaptor DataSet
ADO.NET New Features - DbProviderFactory CreateCommand CreateCommandBuilder CreateConnection CreateDataAdaptor CreateParameter
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 DbConnection conn = 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();
ADO.NET New Features – SqlConnection Asynchronous Operation Support Failover Partner MultipleActiveResultSets (MARS) Connection String Builders
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>
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
ADO.NET New Features – SqlCommand Async Patterns (1)
// Start a non-blocking executionIAsyncResult iar = cmd.BeginExecuteReader();
// Do work while command running ….
// Block the execution until doneSqlDataReader reader =
cmd.EndExecuteReader(iar);
// Process data hereWorkWithData(reader);
ADO.NET New Features – SqlCommand Async Patterns (2)
// Start a non-blocking executionIAsyncResult iar = cmd.BeginExecuteReader();
do {
// Do work while command running ….} while (!iar.IsComleted);
// Sync up and process dataSqlDataReader reader = cmd.EndExecuteReader(iar);
// Process data hereWorkWithData(reader);
ADO.NET New Features – SqlCommand Async Patterns (3)
// Start a non-blocking executionIAsyncResult iar = cmd.BeginExecuteReader( new
AsyncCallback(WorkWithData),cmd);
// … later in your code
Public void WorkWithData(IAsyncResult ar){
// Retrieve the context of the callSqlCommand cmd = (SqlCommand) ar.AsyncState;
// Complete the async operationSqlDataReader reader = cmd.EndExecuteReader(ar);
}
ADO.NET New Features – TransactionScope Supports Dispose Pattern Determines if local or distributed
transaction are needed Objects that support ITransaction can
participate
ADO.NET New Features – TransactionScopeusing (TransactionScope ts = new System.Transactions.TransactionScope()) { bool success = true;
using (SqlConnection conn = new SqlConnection(ConnString)) { SqlCommand cmd = 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(); }
ADO.NET New Features - SqlDataAdaptor New Properties
AcceptChangesDuringUpdate FillLoadOption▪ OverwriteChanges (Current and Orginal)▪ PreserveChanges (Original Only)▪ Upsert (Current Version of row)
ReturnProviderSpecificTypes UpdateBatchSize
ADO.NET New Features - DataSet New Properties
RemotingFormat▪ Binary or Xml
SchemaSerializationMode (IncludeShema/ExcludeSchema)
New Methods CreateDataReader – Creates a reader off
a Data Table
ADO.NET New Features – DataSet CreateDataReader
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 recordDataTableReader reader = data.CreateDataReader();
do{
while (reader.Read())Response.Write(String.Format("{0} <br>",
reader[1]));
Response.Write("<hr>");} while (reader.NextResult());
reader.Close();
ADO.NET New Features
Binding Model Changes
New Data Source Properties Binding Expressions Data Source Controls
Binding Model Changes – New Data Source Properties DataSourceID AppendDataBoundItems
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”)%>
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”)%>
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%>
Binding Model Changes – Data Source Controls Tabular Data Source Controls
AccessDataSource ObjectDataSource SqlDataSource
Hierarchical Data Source Controls SiteMapDataSource XmlDataSource
DataSourceView
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)
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
Binding Model Changes – Data Source Controls – SqlDataSource (3)
Command contain own set of parameters
Declarative Parameters ControlParameter CookieParameter FormParameter ProfileParameter QueryStringParameter SessionParameter
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
Binding Model Changes
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
Adam Calderon More info on InterKnowlogy:
www.InterKnowlogy.com Contact Information
E-mail: [email protected]: 760-930-0075 x274Blog: http://blogs.InterKnowlogy.com/AdamCalderon
About Adam Calderon Microsoft MVP – C# Microsoft UI Server Frameworks Advisory Council Developer / Author / Speaker / Teacher