The 'NET framework

1
The .NET framework

• Course Organisers
• Bruce Scharlau (CS3514)
• Judith Masthoff (CS5540)

2
Background

• Client-side scripting (e.g. Javascript)
• Server-side scripting
• PERL (Good at Pattern matching)
• ColdFusion (Looks like HTML)
• Python (0bject oriented, started from Unix)
• PHP
• Active Server Pages (ASP)

3
.NET What is it?

• Software platform
• Language neutral
• Not a language!
• Framework Class Library Object oriented
  collection of reusable classes
• Common Language Runtime

4
.NET What is it?

• Designed to solve the challenges of
• Software integration
• Language silos (no need to learn library for
  each new language)
• Memory bugs
• Security
• And more..

5
.NET What is it?
Visual Studio .NET Or Web Matrix
Common Language Runtime
6
CLR

• Common Language Runtime
• Compilation (Just-in-time compiler)
• Code execution
• Memory management
• Thread execution
• Error-handling
• Security support
• Initially only for Windows, but others have
  appeared (Mono for Linux, Rotor for Mac).

7
CLS and CTS

• Common Language Specification (CLS)Set of
  specifications that language and library
  designers need to follow
• Common Type System (CTS) Implements various
  types (int, double, etc) and operations on those
  types

8
Compilation in .NET
Code in another .NET Language
Code in VB.NET
Code in C
Appropriate Compiler
VB.NET compiler
C compiler
IL(Intermediate Language) code
CLR (Common Language Runtime) just-in-time
compilation
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Intermediate Language

• .NET languages are compiled to an Intermediate
  Language (IL), not machine code.
• CLR recompiles the IL code into machine code,
  just-in-time (JIT) done when a function is
  called.
• The JIT code stays in memory for subsequent calls
  (if memory allows).

10
Languages supported

• Microsoft providesVisual Basic, C, C, J,
  Jscript
• Others are buildingAPL, Pascal, Cobol, Eiffel,
  Haskell, ML, Oberon, Perl, Python, Scheme,
  Smalltalk ..

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C

• New language developed specifically for .NET
• Looks like JAVA or C
• Simpler than C

12
Framework Class Library

• Common library
• across languages (VB, C, C, ..)
• across application types (Windows, Web, ..)

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Framework Class Library
System.Web
System.Windows.Forms
Services
UI
Design
ComponentModel
Description
HtmlControls
Discovery
WebControls
Protocols
System.Drawing
Caching
Security
Drawing2D
Printing
Configuration
SessionState
Imaging
Text
System.Data
System.Xml
OleDb
SqlClient
XSLT
Serialization
Common
SQLTypes
XPath
System
Collections
IO
Security
Runtime
InteropServices
Configuration
Net
ServiceProcess
Remoting
Diagnostics
Reflection
Text
Serialization
Globalization
Resources
Threading
14
ASP.NET

• ASP.NET, the platform services that allow to
  program Web Applications and Web Services in any
  .NET language
• ASP.NET uses .NET languages to generate HTML
  pages. HTML page is targeted to the capabilities
  of the requesting Browser.
• ASP.NET Program is compiled into a .NET class
  and cached the first time it is called. All
  subsequent calls use the cached version.

15
ASP.NET

• Logical Evolution of ASP
• Supports multiple languages
• Improved performance
• Control-based, event-driven execution model
• More productive
• Cleanly encapsulated functionality

16
Web Applications

• User browses to a web page
• Code runs on the server
• Pure HTML is sent to the browser
• Nothing to install on client machine
• Programming model is just like a Windows
  application
• Event handling

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Web Applications

• Separation of UI and code
• Helps productivity
• Allows better team work
• Drag and drop web controls
• Validation controls
• Client and server side validation
• Rich controls
• Calendar, datagrid, etc
• All represented as HTML

18
Web Services

• It is just an application
• that exposes its features and capabilities over
  the network
• using XML
• to allow for the creation of powerful new
  applications that are more than the sum of their
  parts

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Windows Forms

• Consistent way to create Windows applications
  across languages
• Same designers
• Same event model
• Same controls
• Powerful and useful controls
• Simplified deployment
• But user must have .NET Framework

20
Mobile Development

• Visual Studio supports building for smart
  devices.
• Same tools, controls, classes
• Leverage skills
• Emulator included in Visual Studio

21
ADO.NET

• Language neutral data access
• New objects (e.g., DataSets)
• Separates connected / disconnected issues
• Uses same types as CLR
• Great support for XML

22
Visual Studio.NET

• Development tool that contains a rich set of
  productivity and debugging features
• We will be using a freeware alternative Web
  Matrix.

23
.NET What is it?
Visual Studio .NET Or Web Matrix
Common Language Runtime
24
Conclusions

• .Net provides way of implementing enterprise
  systems
• Different parts can be written in different
  languages, run in different environments (web,
  windows, etc), and still reuse code and skills

25
Tutorials

• In the next three weeks, you will build an
  ASP.NET front end, using C.
• Tutorial 1 Providing a user-interface for
  the application, and logic.
• Tutorial 2 Connecting your application to
  a database.
• Tutorial 3 Cleaning up the application,
  by separating the C code out.