cover topics asp.net

2.  ASP.Net is a web development platform, which provides a
programming model, a comprehensive software infrastructure
and various services required to build up robust web application
for PC, as well as mobile devices.
 ASP.Net works on top of the HTTP protocol and uses the HTTP
commands and policies to set a browser-to-server two-way
communication and cooperation.
 ASP.Net is a part of Microsoft .Net platform.
 ASP.Net applications are complied codes, written using the
extensible and reusable components or objects present in .Net
framework.
 These codes can use the entire hierarchy of classes in .Net
framework.

3.  The ASP.Net application codes could be written in either of the
following languages:
C#
Visual Basic .Net
Jscript
J#
 ASP.Net is used to produce interactive, data-driven web
applications over the internet. It consists of a large number of
controls like text boxes, buttons and labels for assembling,
configuring and manipulating code to create HTML pages.

4. HTTP Request
HTTP Response
CLR
DATABASE
ASP.NET
.NET Framework
HTTP Request In HTTP Response Out
.ASPX .HTML
Internet Information
Server
Web Server
Client

5.  ASP.Net web forms extend the event-driven model of interaction
to the web applications. The browser submits a web form to the
web server and the server returns a full markup page or HTML
page in response.
 All client side user activities are forwarded to the server for
stateful processing. The server processes the output of the client
actions and triggers the reactions.

6.  . ASP.Net framework helps in storing the information regarding the state of the
application, which consists of:
 Page state
 Session state
 The page state is the state of the client, i.e., the content of various input fields in
the web form.
 The session state is the collective obtained from various pages the user visited and
worked with, i.e., the overall session state. To clear the concept, let us take up an
example of a shopping cart as follows.
 User adds items to a shopping cart. Items are selected from a page, say the items
page, and the total collected items and price are shown in a different page, say the
cart page. Only HTTP cannot keep track of all the information coming from
various pages. ASP.Net session state and server side infrastructure keeps track of
the information collected globally over a session.

7.  Now, HTTP is a stateless protocolThe ASP.Net
runtime carries the page state to and from the
server across page requests while generating the
ASP.Net runtime codes and incorporates the state
of the server side components in hidden fields.
 This way the server becomes aware of the overall
application state and operates in a two-tiered
connected way.

8.  The ASP.Net component model provides various building
blocks of ASP.Net pages. Basically it is an object model,
which describes:
 Server side counterparts of almost all HTML
elements or tags, like <form> and <input>.
 Server controls, which help in developing
complex user-interface for example the
Calendar control or the Gridview control.

9.  ASP.Net is a technology, which works on the .Net framework that
contains all web-related functionalities.
 The .Net framework is made of an object-oriented hierarchy.
 An ASP.Net web application is made of pages. When a user
requests an ASP.Net page, the IIS delegates the processing of the
page to the ASP.Net runtime system.
 The ASP.Net runtime transforms the .aspx page into an instance
of a class, which inherits from the base class Page of the .Net
framework.
 Therefore, each ASP.Net page is an object and all its components
i.e., the server-side controls are also objects.

10.  Before going to the next session on Visual
Studio.Net, let us look at the various
components of the .Net framework 3.5. The
following table describes the components of
the .Net framework 3.5 and the job they
perform:

11. (1) Common Language Runtime or CLR
 It performs memory management, exception handling, debugging, security
checking, thread execution, code execution, code safety, verification and
compilation.Those codes which are directly managed by the CLR are called the
managed code. When the managed code is compiled, the compiler converts the
source code into a CPU independent intermediate language (IL) code. A Just in time
compiler (JIT) compiles the IL code into native code, which is CPU specific.
(2) .Net Framework Class Library
 It contains a huge library of reusable types . classes, interfaces, structures and
enumerated values, which are collectively called types.

12. (3) Common Language Specification
 It contains the specifications for the .Net supported languages and
implementation of language integration.
(4) Common Type System
 It provides guidelines for declaring, using and managing types at runtime,
and cross-language communication.
 Metadata and Assemblies
 Metadata is the binary information describing the program, which is
either stored in a portable executable file (PE) or in the memory.
Assembly is a logical unit consisting of the assembly manifest, type
metadata, IL code and set of resources like image files etc.
(5) Windows Forms
 This contains the graphical representation of any window displayed in the
application.

13. (6) ASP.Net and ASP.Net AJAX
 ASP.Net is the web development model and AJAX is an extension of
ASP.Net for developing and implementing AJAX functionality. ASP.Net
AJAX contains the components that allow the developer to update data
on a website without a complete reload of the page.
(7) ADO.Net
 It is the technology used for working with data and databases. It provides
accesses to data sources like SQL server, OLE DB, XML etc. The ADO .Net
allows connection to data sources for retrieving, manipulating and
updating data.
(8) Windows Workflow Foundation (WF)
 It helps in building workflow based applications in Windows. It contains
activities, workflow runtime, workflow designer and a rules engine.

14. (9)Windows Presentation Foundation
 It provides a separation between the user
interface and the business logic. It helps in
developing visually stunning interfaces using
documents, media, two and three dimensional
graphics, animations and more.
(10) Windows Communication Foundation (WCF)
 It is the technology used for building and running
connected systems.

15. (11) Windows CardSpace
 It provides safety of accessing resources and sharing personal
information on the internet.
(12) LINQ
 It imparts data querying capabilities to .Net languages using a
syntax which is similar to the tradition query language SQL.

16.  ASP.Net provides an abstraction layer on top of HTTP on which
the web applications are built. It provides high-level entities like
classes and components within an object-oriented paradigm.
 The key development tool for building ASP.Net applications and
front ends is Visual Studio. In these tutorials, we will work on
Visual Studio 2008.
 Visual Studio is an integrated development environment for
writing, compiling and debugging the code. It provides a
complete set of development tools for building ASP.Net web
applications, web services, desktop applications and mobile
applications.

17.  The new project window allows choosing an
application template from the available
templates.

19.  When you start a new web site, ASP.NET provides the starting folders and
files for the site, including two files for the first web form of the site.
 The file named Default.aspx contains the HTML and asp code that defines
the form, and the file named Default.aspx.cs (for C# coding) or the file
named Default.aspx.vb (for vb coding) contains the code in the language
you have chosen and this code is responsible for the form's works.
 The primary window in the Visual Studio IDE is the Web Forms Designer
window. Other supporting windows are the Toolbox, the Solution Explorer,
and the Properties window. You use the designer to design a web form, to
add code to the control on the form so that the form works according to
your need, you use the code editor.

20. The following are the ways to work with different
windows:
 To change the Web Forms Designer from one view to
another, click on the Design or source button.
 To close a window, click on the close button on the
upper right corner and to redisplay, select it from the
View menu.
 To hide a window, click on its Auto Hide button; the
window changes into a tab, to redisplay again click
on the Auto Hide button again.
 To size a wind just drag it.

21.  A typical ASP.Net application consists of many items: the web content files (.aspx), source files
(e.g., the .cs files), assemblies (e.g., the .dll files and .exe files), data source files (e.g., .mdb
files), references, icons, user controls and miscellaneous other files and folders. All these files
that make up the website are contained in a Solution.
 When a new website is created VB2008 automatically creates the solution and displays it in the
solution explorer.
 Solutions may contain one or more projects. A project contains content files, source files, and
other files like data sources and image files. Generally the contents of a project are compiled into
an assembly as an executable file (.exe) or a dynamic link library (.dll) file.
 Typically a project contains the following content files:
 Page file (.aspx)
 User control (.ascx)
 Web service (.asmx)
 Master page (.master)
 Site map (.sitemap)
 Website configuration file (.config)

22.  The application is run by selecting either
Start or Start Without Debugging from the
Debug menu, or by pressing F5 or Ctrl-F5.
The program is built i.e. the .exe or the .dll
files are generated by selecting a command
from the Build menu.

23. HTMLASPX
C#, VB,
C++, or
.NET
language
(Code behind)
+ =
Web Page
CSSHTML JavaScript+ + =
Bryan Jenks
© Integrated Ideas 2005
Server Side:
Client Side:

24. Following are the different stages of an ASP.Net page:
 Page request . when ASP.Net gets a page request, it decides whether to parse and compile the
page or there would be a cached version of the page; accordingly the response is sent
 Starting of page life cycle . at this stage, the Request and Response objects are set. If the request
is an old request or post back, the IsPostBack property of the page is set to true. The UICulture
property of the page is also set.
 Page initialization . at this stage, the controls on the page are assigned unique ID by setting the
UniqueID property and themes are applied. For a new request postback data is loaded and the
control properties are restored to the view-state values.
 Page load . at this stage, control properties are set using the view state and control state values.
 Validation . Validate method of the validation control is called and if it runs successfully, the
IsValid property of the page is set to true.
 Postback event handling . if the request is a postback (old request), the related event handler is
called.
 Page rendering . at this stage, view state for the page and all controls are saved. The page calls
the Render method for each control and the output of rendering is written to the OutputStream
class of the Page's Response property.
 Unload . the rendered page is sent to the client and page properties, such as Response and
Request are unloaded and all cleanup done.

25. ProcessRequest
DeterminePostBackMode
OnPreInit
ApplyMasterPage
(recursive)
PerformPreInit
Load
ProcessPostData
OnInitComplete
LoadControlState
LoadViewState
RaiseChangedEvents
RaisePostbackEvent
OnLoadComplete
PreRender (recursive)
CreateChildControls
Render (recursive)
SaveAllState
SaveControlState
SaveViewState
Bryan Jenks
© Integrated Ideas 2005

26. O b j e c t N a m e D e s c r i p t i o n
R e q u e s t U s e d t o a c c e s s i n f o r m a t i o n p a s s e d b y a n
H T T P r e q u e s t .
R e s p o n s e U s e d t o c o n t r o l t h e i n f o r m a t i o n s e n t t o t h e
c l i e n t .
S e r v e r U s e d t o a c c e s s m e t h o d s a n d p r o p e r t i e s o n t h e
s e r v e r .

27. H T M L S e r v e r
C o n t r o l
D e s c r ip t io n
H t m l A n c h o r N a v i g a t i o n l i n k .
H t m l B u t t o n C u s t o m i z a b l e i n p u t b u t t o n .
H t m l T a b l e P r o g r a m m a t i c a l l y b u i l t t a b l e .
H t m l I n p u t F i l e H a n d l e s u p l o a d i n g o f f i l e s f r o m c l i e n t t o s e r v e r .
H t m l I m a g e R e n d e r s i m a g e s .
H t m l F o r m U s e r - i n p u t f o r m .

28. W e b S e r v e r
C o n t r o l
D e s c r i p t i o n
A d R o t a t o r P r e s e n t s a d i m a g e s a n d a d b a n n e r s .
D a t a G r i d D i s p l a y s t a b u l a r d a t a a n d s u p p o r t s s e l e c t i n g , s o r t i n g
a n d e d i t i n g d a t a .
T e x t B o x E n a b l e s u s e r t o e n t e r t e x t .
H y p e r L i n k C r e a t e s a l i n k t o a n o t h e r d o c u m e n t .
D r o p D o w n L i s t P r o v i d e s a s i n g l e - s e l e c t d r o p - d o w n l i s t .
C a l e n d a r D i s p l a y s a m o n t h c a l e n d a r f r o m w h i c h u s e r s c a n
s e l e c t d a t e s .

29. S e r v e r C o n t r o l D e s c r i p t i o n
R e q u i r e d F i e l d V a l i d a t o r C h e c k s t h a t t h e u s e r d o e s n o t l e a v e a
f i e l d b l a n k .
C o m p a r e V a l i d a t o r C o m p a r e s a n i n p u t v a l u e w i t h
a n o t h e r v a l u e . T h e v a l u e b e i n g
c o m p a r e d t o m a y b e a n o t h e r
c o n t r o l ’ s i n p u t v a l u e .
R a n g e V a l i d a t o r C h e c k s t h a t a u s e r ’ s e n t r y i s w i t h i n a
s p e c i f i e d r a n g e .
R e g u l a r E x p r e s s i o n V a l i d a t o r C h e c k s t h a t t h e e n t r y m a t c h e s a
r e g u l a r e x p r e s s i o n p a t t e r n .
V a l i d a t i o n S u m m a r y D i s p l a y s t h e v a l i d a t i o n e r r o r s f o r a l l
t h e v a l i d a t i o n c o n t r o l s o n a p a g e .

30. 1 <%@ Page Language="JScript" %>
2 <%@ Import Namespace="System" %>
3
4 <%-- Fig. 23.19: optionsPage.aspx --%>
5 <%-- Page that presents a list of language options. --%>
6
7 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
8 "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
9
10 <html>
11 <head>
12 <title>Options Page</title>
13
14 <script runat = "server">
15
16 // event handler for Load event
17 var books : Hashtable = new Hashtable();
18
19 function Page_Load( sender : Object, events : EventArgs ) : void
20 {
21 // if page is loaded due to postback, load session
22 // information, hide language options from user
23 books.Add( "C#", "0-13-062221-4" );
24 books.Add( "C++", "0-13-089571-7" );
25 books.Add( "C", "0-13-089572-5" );

31. 26 books.Add( "Python", "0-13-092361-3" );
27
28 if ( IsPostBack )
29 {
30 // display components that contain
31 // session information
32 welcomeLabel.Visible = true;
33 languageLink.Visible = true;
34 recommendationsLink.Visible = true;
35
36 // hide components
37 submitButton.Visible = false;
38 promptLabel.Visible = false;
39 languageList.Visible = false;
40
41 // set labels to display Session information
42 if ( languageList.SelectedItem != null )
43 {
44 welcomeLabel.Text +=
45 languageList.SelectedItem.ToString() + ".";
46 }
47 else
48 {
49 welcomeLabel.Text += "no language.";
50 }

32. 51
52 idLabel.Text += "Your unique session ID is: " +
53 Session.SessionID;
54
55 timeoutLabel.Text += "Timeout: " +
56 Session.Timeout + " minutes";
57 } // end if
58 } // end Page_Load
59
60 // when user clicks Submit button,
61 // store user's choice in session object
62 function submitButton_Click (
63 sender : Object, events : EventArgs ) : void
64 {
65 if ( languageList.SelectedItem != null )
66 {
67 var language : String =
68 languageList.SelectedItem.ToString();
69
70 // note: must use ToString method because the hash table
71 // stores information as objects
72 var ISBN : String = books[ language ].ToString();
73
74 // store in session as name-value pair
75 // name is language chosen, value is

33. 7 6 T e x t = " W e c a n n o t g i v e y o u t h a t m a n y s c o o p s . "
7 7 r u n a t = " s e r v e r " / >
7 8
7 9 < c e n t e r >
8 0 < h 1 > < a s p : l a b e l i d = " m e s s a g e " r u n a t = " s e r v e r " / > < / h 1 >
8 1 < / c e n t e r >
8 2
8 3 < / f o r m >
8 4 < / b o d y >
8 5 < / h t m l >