ASP'NET

1
ASP.NET
2
Microsoft .NET Framework
XML Web Services
Web Forms
Windows Forms
ASP.NET
C VB.NET J C
Data and XML Classes
Base Framework Classes
Common Language Runtime
3
Overview
MyPage.aspx
HttpHandler(.aspx)
Page
HtmlForm
Http Application
Button
TextBox
Http Module (Authorization)
Http Module (Authentication)
Http Module (OutputCache)
ASP.NET Runtime (ISAPI)
IIS (Web Server)
Internet
4
ASP.NET Application

• Resides in a folder on a web server (IIS)
• The web site is configured for ASP.NET, meaning
  it is set to handle .aspx page requests by
  sending them to the ASP.NET Runtime
• web.config application configuration file
• Aspx files
• .dll assembly of compiled codebehind and other
  classes

5
Global Programming (Global.asax)

• Define Application Global methods, constants,
  variables
• Global Event Handling
• Application_Start
• Session_Start
• Application_BeginRequest
• Application_AuthenticateRequest
• Useful for setting up custom Page.User and roles
• Application_Error
• Session_End
• Application_End

6
ASP.NET Application Configuration

• Settings in machine.config
• Settings in web.config
• ltcustomErrorsgt
• lttracegt
• ltsessionStategt
• ltappSettingsgt
• ltaddgt
• key attribute
• value attribute
• Security Settings
• ltauthenticationgt
• ltauthorizationgt
• ltidentitygt

7
ASP.NET Security Configuration

• ltauthenticationgt
• Windows
• Forms
• Passport
• ltauthorizationgt
• ltallowgt
• ltdenygt
• ltidentitygt
• impersonate attribute
• userName and password attributes
• Can be stored encrypted in the registry

8
ASP.NET Application Security

• Page.User
• Identity
• GenericPrincipal and Roles
• PrincipalPermission and IsInRole
• IIS Configuration
• Interaction with Application Security
• Integrated, Basic, Digest, Kerberos
• Accessing Backend Resources (Architecture)

9
System.Web.UI.Page

• ASP.NET Web Page Consists of
• An .aspx page
• An optional .NET class file containing code for
  that page
• Any user controls used by the page
• Think of the page as an object
• Controls are object variables
• Access them in code
• Inline (Inferior)
• Code is interspersed with HTML
• Code Behind (Superior)
• Code resides in a separate class file

10
The Page Directive

• Defines page-specific (.aspx file) attributes
  used by the ASP.NET page parser and compiler.
• Example showing an .aspx page mapped to its
  code behind
• lt_at_ Page Codebehind"WebForm1.aspx.vb"
  inherits"AspNet.WebForm1" gt

11
Server-Side Events
Client
Server
MyPage.aspx
Private Sub btnGo_Click() End Sub
Search
PostBack
12
Event flow in ASP.NET pages (.aspx)

• Application Level Events (Global.asax)
• Page_Init page and controls are initialized
• Page_Load all the controls and page are loaded
• Change events for controls are processed
• Click events for controls are processed
• Page_PreRender page is about to render
• Page_Unload page is unloaded from memory

13
Controls

• WebForm Controls
• HTML Controls
• Web User Controls
• Custom Controls

14
Whats in the Toolbox?

• WebForm Controls
• TextBox, Label, Hyperlink, Etc
• DropDownList, DataGrid, DataList, Etc
• HTML Controls (Client or Server)
• ADO.NET Design Controls
• System Components
• Validation Controls

15
WebForm Vs HTML Controls

• Both have the following benefits
• An object model that you can program against on
  the server 1
• A set of events for which you can write sever
  side event handlers. 1
• The ability to handle events in client script . 1
• Automatic maintenance of the control's state
  (ViewState). 1
• Interaction with validation controls so you can
  easily verify that a user has entered appropriate
  information into a control. 1
• Data binding to one or more properties of the
  control. 1
• Support for HTML 4.0 styles if the Web Forms page
  is displayed in a browser that supports cascading
  style sheets. 1
• Pass-through of custom attributes. 1
• HTML Controls Advantage
• Object model with a one-to-one mapping to HTML
  elements 1
• WebForm Controls Advantage
• A richer object model that provides type-safe
  programming capabilities. 1
• Automatic browser detection. 1
• For some controls, the ability to define your own
  look for the control using templates. 1
• For some controls, the ability to specify whether
  a control's event causes immediate posting to the
  server or is instead cached and raised when the
  form is submitted. 1
• Ability to pass events from a nested control
  (such as a button in a table) to the container
  control. 1

1 Ref Introduction to ASP.NET Server
Controlsms-help//MS.VSCC.2003/MS.MSDNQTR.2003FEB
.1033/vbcon/html/vbconintroductiontowebformscontro
ls.htm2 See Also ASP.NET Server Controls
Recommendationsms-help//MS.VSCC.2003/MS.MSDNQTR.
2003FEB.1033/vbcon/html/vbconchoosingwebformscontr
ols.htm
16
Validation Controls

• RequiredFieldValidator
• CompareValidator
• RangeValidator
• RegularExpressionValidator
• CustomValidator
• ValidationSummary

17
Validation Controls Common Properties

• ControlToValidate ? This property lets the
  validator know which control it has to validate.
  (It binds the validator to that control and then
  the validator monitors that control.)
• ErrorMessage ? This is the error message that
  appears in the validation summary when the
  control being validated violates the condition
  set by the validator.
• Text ?Information that gives guidance to correct
  the error.

18
Page.Validate() and Page.IsValid

• They allow you to trigger validation from
  different points in your code
• Validate() must be called before checking IsValid

19
DataBinding

• Populating Controls with Data
• Single-Value vs. Multi-Record
• Design-time vs. Runtime Binding

20
How State is Managed in a Stateless World

• Posted Data Handling
• ViewState
• Webforms automatically handles form data and
  persists it across requests
• Hidden field with encoded data
• Session (in memory or a database)
• Cache

21
OutputCache

• Cache the HTML output of a page
• Increases performance
• Duration
• Location
• VaryByParam

22
Debugging ASP.NET

• Using Visual Studio .NET debugging tools
• Breakpoints
• Stop keyword
• System.Diagnostics.Debug
• Command/Immediate Windows
• Watch/Quick Watch
• Autos/Locals Windows
• Trace
• Client Script Debugging
• Active Documents
• Debugger keyword

23
Deployment

• Can be XCopyd
• Usually only the .aspx pages and the compiled
  codebehind assembly