ASP.NET 2.0 Tips

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ASP.NET 2.0 Tips TricksTips Tricks for
ASP.NET 2.0

• Rob Howard
• Telligent
• Microsoft Regional Director

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For more information

• Rob Howard
• Email rhoward_at_telligent.com
• Website telligent.com
• Blog weblogs.asp.net/rhoward
• Telligent
• Community Server (communityserver.org)
• Custom Application Development (ASP.NET)

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Agenda

1. Cross Page Posting
2. Validation Groups
3. Wizard Control and Profile Registration
4. Secure Connection String Storage
5. Config-based Control Registration
6. Caching Features
7. Client Script Goodies, Client Callbacks
8. XML Databinding to build a Blog Reader
9. URL Rewriting
10. Site Map

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1. Cross Page Posting

• Problem
• Postback model isnt always desired
• Scenario Search or lookup button at top of page
• New PostBackUrl property
• ltaspbutton PostBackUrlb.aspx runatserver/gt
• Declaratively or programmatically set
• Page posted to has strongly typed access
• Access controls via Page.PreviousPage property
• lt_at_ PreviousPage VirtualPatha.aspx gt

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Cross-Page Postback Example

• lt!-- Page1.aspx --gt
• lthtmlgt
• ltbodygt
• ltform runatservergt
• ltaspbutton textSame Page
  OnClickBtn1_Click runatserver/gt
• ltaspcalendar idMyCalendar
  runatserver/gt
• ltaspbutton textPage 2
  PostBackUrlpage2.aspx runatserver/gt
• lt/formgt
• lt/bodygt
• lt/htmlgt
• Page2.aspx
• Dim MyCalendar as Calendar PreviousPage.FindCont
  rol(MyCalendar)
• Label1.Text You selected
  MyCalendar.SelectedDate

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Cross Page Posting
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2. Validation Groups

• Problem
• Today validation controls apply all or nothing
• ASP.NET 2.0 ValidationGroup property
• Supported by all Validation and Postback controls
• Controls in ValidationGroup validate with
  postback
• Programmatic Support for Validating Groups
• If (Page.Validate(group_name)) Then
• Page.IsValid evaluates ValidationGroup Postback

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ValidationGroup Example

• ltform runatservergt
• ltasptextbox idTextBox1
  runatserver/gt
• ltasprequiredfieldvalidator
  ValidationGroupGroup1
• ErrorTextNeed to Fill in Value!
• ControlToValidateTextBox1
• 
  runatserver/gt
• ltasptextbox idTextBox2 runatserver/gt
• ltasprequiredfieldvalidator
  ValidationGroupGroup2
• ErrorTextNeed to Fill in Value!
• ControlToValidateTextBox2
• 
  runatserver/gt
• ltaspbutton textGroup1
  ValidationGroupGroup1 runatserver/gt
• ltaspbutton textGroup2 ValidationGroupGro
  up2 runatserver/gt
• lt/formgt

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Validation Groups
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3. Wizard Control

• Problem
• Difficult to build Wizard style UI today
• Enables linear and non-linear navigation
• Developer defines templated steps within
  control
• Control state maintained throughout wizard steps
• Flexible Wizard Control Navigation Model
• MoveTo(wizardStep), ActiveStepIndex, etc
• Events can fire on steps and completion

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ltASPWizardgt Example

• ltaspwizard idWizard1 runatserver
  OnFinishButtonClickFinishBtn_Clickgt
• ltWizardStepsgt
• ltaspWizardStep idWizardStep1
  titleStep 1gt
• Enter Name ltasptextbox
  idName runatserver/gt
• lt/aspWizardStepgt
• ltaspWizardStep idWizardStep1
  titleStep 2gt
• Enter State ltasptextbox
  idState runatserver/gt
• lt/aspWizardStepgt
• ltaspWizardStep idDone titleCompletegt
• Congrats! The
  registration is complete!
• lt/aspWizardStepgt
• lt/WizardStepsgt
• lt/aspwizardgt
• Sub FinishBtn_Click(Sender as Object, E as
  WizardNavigationEventArgs)
• Label1.Text Hi Name.Text you are
  from State.Text
• End Sub

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Wizard Control
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4. Connection String Storage

• Persistence and declarative referencing
• Stored in .config
• Avoid hard-coding within pages/code
• Can be optionally encrypted
• Built-in design time support
• Promote use for best practices
• Enable optional encrypting of values in config
• Admin Support
• MMC Admin Tool Support
• Configuration API Support

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Config Connection Strings
Web.config
ltconnectionStringsgt ltadd name"pubs
ProviderName connectionString
/gt lt/connectionStringsgt
Page.aspx
ltaspSqlDataSource IdMySource
ConnectionStringlt connectionStringspubs gt
SelectCommandselect au_id from authors
runatserver/gt
Code.vb
Dim connstr As String ConfigurationSetting
s.ConnectionStrings(pubs)
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Connection Strings
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5. Web.Config Registration of Controls

• Server controls can now be registered within
  web.config files instead of on every page
• Full Visual Studio support w/ intellisense

lt!-- Web.Config --gt ltcontrolsgt ltadd
tagPrefix"acme" tagName"uc" src"controls/uc.asc
x" /gt ltadd tagPrefix"my" namespace"MyControl
s.Basic" assembly"MyControls" /gt lt/controlsgt
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Control Registration
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6. Caching

• SQL 7 2000 Support
• Table change dependencies on SQL 7 2000
• Requires ltcachinggt configuration settings
• One-time setup of SQL Server database
• Polling model
• SQL Server Yukon
• Result Set dependencies for SQL Yukon
• Supported through ADO.NET SqlCommand
• No setup required
• Notification model

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SQL Server 7 2000

• Table level notifications only
• Notification when data in table changes
• Row-level notification is not supported
• Requires one time setup of SQL 7 / 2000
• Triggers on tables that participate
• Stored procedures called to check
• Of Note
• Entries in cache table lt of tables in DB
• Entries in cache items in cache table

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Data Caching
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How it works SQL 7 2000
ASP.NET
SQL Server
Cache
Northwind Database
Products table
SqlCacheDependency
N n1
data a
DataSet
ChangeNotification table
tableName changeId

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aspnet_regsql.exe
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7. Client Script Goodies

• Client-side click event handlers on controls
• Focus mechanisms
• Page.SetFocus(control)
• TextBox.Focus()
• Default button and focus
• ltform DefaultFocuscontrol1 runatservergt
• ltform DefaultButtonbutton1 runatservergt

ltaspbutton TextPush Me!
OnClickButton1_Click
OnClientClickClientButton1_Click
runatserver /gt
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Client Script Goodies

• Validation Error Focus
• SetFocusOnError property
• Auto-scroll maintenance on postback
• Ideal for large pages no code required
• Simplified Client Script Registration
• Page.ClientScript helper methods
• Client-side Event Callbacks
• ICallBackEventHandler interface
• Used by TreeView, GridView controls

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Client Script Goodies
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8. XML Databinding

• ltaspXmlDataSourcegt control enables data source
  binding against XML files
• Optional XPath expression to scope results
• ltaspDataListgt supports binding against
  ltaspXMLDataSourcegt
• Use XPath(expression) statement in templates
• XPathSelect(expression) selects a node list
• Combine two to build simple RSS Reader

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RSS Reader
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9. URL Rewriting

• Enable vanity URLs
• Eliminate ugly query string URLs
• Simplifies customer navigation experience
• Possible in ASP.NET 1.1
• Required custom code
• Ex., Community Server
• ASP.NET 2.0
• Simply edit configuration file
• Add/Remove/Clear mappings

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URL Rewriting
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10. Site Map

• How to manage all the site urls
• Many navigation points
• What is the relationship between these points
• Possible in ASP.NET 1.1
• Write a complete site map
• Ex., Community Server
• ASP.NET 2.0
• Site Map is a built in feature (Provider based)
• Makes adding URLs/Pages unbelievably easy

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Site Map
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Summary

• Enormous number of new features in ASP.NET 2.0
• Tons of additional cool features out there
• Visit http//beta.asp.net/quickstarts to try out
  hundreds of samples online
• Download these slidesdemos from
  http//www.rob-howard.net

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10. Dynamic Master Pages

• Master pages encapsulate layout
• Enforce a consistent look and feel across pages
• Master pages can be dynamically chosen
• Scenario Per browser type or per customer type
• Two mechanisms to set dynamically change master
• 1) Set Page.MasterPageFile property in
  Page_PreInit event
• 2) Device Filter lt_at_ page iemasterpagefileie.
  master gt

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Dynamic MasterPages
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10 Localization

• Whidbey supports nice localization model
• Store strings and values in a separate .resx file
  
• Culture and language settings
• programmatically and declaratively set
• Override InitalizeCulture on the Page class
• lt_at_ Page UIculturevalue gt
• Cool Tip You can set value to auto to have it
  automatically based on the client browsers user
  agent string

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Localization