DotNet

Microsoft .NET

Introduction into the next generation

of Internet Applications







Tuna Oezer

Ex-Program Manager

Runtime Kernel

Outline

 Evolution

 .NET Overview

 .NET Architecture

 Common Language Runtime

 C#

Evolution of the Internet

 1st Generation: 1994 – 1996

 Infrastructure

 Static Pages

 E-mail

 Browsers, Web Servers

 2nd Generation: 1996 – 2000

 Dynamic Pages

 Personalization, e-commerce

 Applets, Databases

The Future of the Internet

 3rd Generation

 Beyond Browsing

 Integration of Internet

 Web Services

 XML Service 3

XML

Server XML

XML Service 2

HTML /XML

XML

Client Service 1

Evolution of the PC

 Past: Desktop is only device



 Future: Many Devices, Mobility

 Desktop

 Notebook

 PDA

 Tablet PC

 TV, Toaster, etc.

Evolution of Hardware

 Moor's Law

 Computing power increases

exponentially

 Computing cost decreases



 Networking

 Broadband network access

 Static connections

 Wireless

Evolution of Software

 From Standalone to Networking

 Necessity to interoperate with many

devices

 Distributed Software

 From Product to Service

 Open Source

 Subscription to software

 Services around software

Microsoft .NET

 Move towards a service oriented

business model

 Provides a platform and tools for

service providers

 Integrate and connect many different

kinds of devices over Internet

Scenario

 Example: Health Care

Scenario

 Example: Health Care

 Smart devices

 Mobility, geographic services

 Medical information is stored online

 Appointments can be scheduled

online (Web Service)

 Authentication, Security

 Broadband, wireless networks

 Interactive user interface

Microsoft’s Vision

 People will use many different kinds

of devices

 Information will be accessible from

anywhere

 Information will stay in digital form

 Companies will offer services via the

web

Guest Speaker

 Bill Gates, Chief Software Architect

Guest Speaker

 Bill Gates, Chief Software Architect

 Platform for Internet and a Variety of

Devices

 Smart devices

 Digital World

 Data, XML, Services

 Need easier development of Internet

applications

 More powerful hardware and networks

Microsoft’s Mission

 Empower people through great

software any time, any place, and on

any device

 Provide a platform for the Internet

 .NET Framework

 Provide tools for developers

 Visual Studio .NET

 Provide data storage and access

 .NET Enterprise Servers

 Provide services over the Web

 Passport, Hotmail, Directory, …

Vision of Software Industry

 .NET vision is shared by many

companies

 Microsoft offers complete solution

 Important differences between

visions:

 “Smart devices” vs. “dumb terminals”

 “Write once run everywhere” vs. adapt to

device and interoperate with others

(“Orchestration”)

Different Approaches

.NET Framework

Desktop, Servers

.NET

Functionality, Power, Features









.NET Compact Framework

Smart Devices (PocketPC, Set

Java

Top Box, etc)









.NET Compact Framework and Other

Pager, Cell Phone, etc.





Reach across device form factors, CPUs, OSes

Open Standards

 .NET is based on open Internet

standards

 .NET itself is an open standard

 ECMA standardization is currently in

progress

Microsoft .NET Includes

 .NET Framework

 Visual Studio .NET

 ASP .NET

 Windows .NET

 .NET Enterprise Servers

 Building Block Services

.NET Architecture

Your Application

and Web Service



Orchestration

Other









Operations

Applications Building Block

Using Your .NET

Framework Services

Service

Windows

CE, 2000, XP, .NET

End-User Public Web Services

Clients Open Internet Protocols

SOAP, SCL, DISCO

HTTP, SMTP, XML, WAP, XSD

.NET Framework

Web User

Services Interface



Data & XML

Base Classes



Common Language Runtime

Orchestration



.NET Building

.NET

Enterprise Block

Framework

Servers Services



Windows (CE, ME, 2000, and .NET)

Base Classes

System

Collections Security

Configuration ServiceProcess

Diagnostics Text

Globalization Threading

IO Runtime

Net InteropServices

Reflection Remoting

Resources Serialization

Web Services

Concept Web Protocol Framework



Data XML Objects



Schema XSD (XML Classes

Schema Definition)





Services SCL (SOAP Methods

Configuration

Language)





Invocation SOAP Calls

XML Built in

 XML Parser is built into .NET

Framework

 XML custom parser automatically

generated from XSD document and

compiled into native code

 SOAP is built into .NET

Common Language Runtime

 Platform for .NET applications

 Provides runtime support

 Provides security features

 Enables interoperation of applications

XML, SOAP, etc.





Other Application Your Application Other Application

(CLR) (CLR) (Other platform)





CLR

Services of the CLR

 Class Loading and Layout

 Garbage collection (dynamic)

 20-40 clock cycles for deallocation,

scalable and multi-processor

 Code Manager (manages execution)

 Exception Manager (based on SEH)

 Type Checker

 Security Engine

 Thread Support

 Debug Engine

 COM Marshaler

One Runtime For All

Languages

 CLR is an open standard

 Any language can make use of CLR

services

 Any language can use classes written

in any other language (consumer)

 Any language can (code) inherit

classes written in any other language

(extender)

 A language can become a provider

Types of Supported

Languages

 Object Oriented

 Procedural

 Functional

 Common Language Specification

 Same Tool can be used for all

languages

Metadata: Creation And Use



Source Reflection

Serialization Code

(e.g. SOAP)

Designers

Compiler

Other

Compiler Debugger





Type Browser Metadata Profiler

(and code)





Schema Proxy Generator

Generator

XML encoding

(SDL or SUDS)

Current List of Languages

 Ada  Java .NET (Rational)

 APL  ML

 Basic (Visual Basic) (MS Research Cambridge)

 C#  Mercury

(Melbourne U.)

 C

 Oberon

 C++ (Zurich University)

 COBOL  Oz

 Component Pascal (Univ of Saarlandes)

(Queensland Univ of Tech)  Perl

 ECMAScript (JScript)

 Python

 Eiffel

(Monash University)  Scheme

 Haskell (Northwestern U.)

(Utrecht University)  SmallTalk

Built-in Support For

 Classes

 Global Procedures, Static, Instance

and Virtual Methods

 Subroutines and Co-routines

 Constructors

 Inheritance (Type and Code)

 Overriding and Overloading

 Access Control and Hiding

 Attributes

All Object Oriented



 All data types are objects, including

Integers, Chars, etc.

 Single Object class for all languages

Value Types

 Represent “primitive” types in an

efficient way

 Extensible

 Boxing and unboxing

Intermediate Language (IL)

 Assembly Language of CLR

 Code is never interpreted



VC Standard JIT

Compiler



VB

Native

IL

Code

...

“Econo”-JIT

Compiler

Script

Verification

 IL is verified by a verifier and

guaranteed to be type safe

 Checks for type casts, memory

initialization, array bounds

 Checks stack operations

Security System

 Permissions

 Grant

 Demand (minimal, optional, refuse)

 Stack walk

 Policy – Set of permissions

 Evidence – Input to policy

 Zones

 Cryptography

 Signed XML – IETF/W3C XMLDSIG

 Fully extensible

Managed vs. Unmanaged

 Managed Code makes use of CLR

services

 Unmanaged Code does not use any

services

 Garbage Collector can be turned off

 CLR offers mechanisms for managed

code to interact with unmanaged code

 Interoperation with hardware specific

code and other platforms

 Ability to reuse old code

Versioning

 Multiple versions of component can

be installed on machine

 A single process can use different

version of component at same time

 Zero-impact installation and

uninstallation (copy)

Runtime Control Flow

Class

Loader

First

reference to

IL to native type

code compiler

Execution

Support

First call to

Managed method

Code Native

Managers Code





Security

CPU

System

Common Language Runtime

Other Classes

Base Classes

Common Language Runtime









Execution

native code

compilers









Security

Support

IL to









GC, stack walker, code manager



Class loader and layout

C#

 Built on top of CLR

 Was designed from ground up to

make use of CLR services

 Component Oriented

 Properties are first class

 Events are first class

Hello World



using System;





class Hello {

static void Main() {

Console.WriteLine(“Hello word”);

}

}

Structure

 Namespaces

 May be nested

 Types

 Members

C# Type System

 All types extend Object

 There are no primitive types

 Implicit boxing and unboxing

C# Types Definitions

 Classes

 Interfaces

 Contain methods, properties, indexers,

events

 Private implementations

 Structs (stack allocated)

 Enums

 Delegates

 Object-oriented function pointers

 Multi-cast

C# Member Definitions

 Constants

 Fields

 Methods (static, instance, virtual)

 Constructors and Destructors

 Properties

 Indexers

 can be overloaded

 Events

 Operators

Properties

class Person {

private string _name;

public string name {

get {

return _name;

}

set {

_name = value;

Console.WriteLine(_name);

}

}

}

Attributes

 Types and members may have

attributes associated with them

 Attributes are themselves defined by

classes, extend System.Attribute

 Extensible

 Type-safe

 Used for XML, SOAP, etc.

Other Features

 Parameter arrays

 Versioning

 new and override

 XML comments

Unsafe Code

 Interop

 Enables pointer arithmetic

 Pinning

Conditional Compilation

 #define, #if, etc.

 Conditional methods

 Attribute Conditional(“Debug”)

 E.g., Assert