Transcript Applet Graphical User Interface Event

Windows Programming
.NET
Overview
Yingcai Xiao
What is a Computer?
From the Webster’s New World Dictionary:
1. A person who computes.
2. A device used for computing (an
electronic machine which by means of
stored instructions and information,
perform rapid, often complex calculations
or compiles, correlates, and selects data).
What is a program and what is programming?
Programs:
stored computer instructions for data
processing.
Programming
= Data Structures + Algorithms
Professor Donald E. Knuth
http://www-cs-faculty.stanford.edu/~knuth/
What is Windows Programming?
Windows Programming:
Program for the Windows platform?
Program for the Internet on the
Windows platform!
What is .NET?
.Net is a framework for developing OSplatform-independent, programminglanguage-independent, web-enabled,
distributed applications.
Traditional Compilation (Linking)
Source Code for Language 1
Source Code for Language 1
Language 1 Compiler on OS1
Language 1 Compiler on OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
Common Binary Code?
OS-Independent Code:
Intermediate Languages
The trend to support OS-independent binary
code is to compile the source code into the binary
format of an intermediate language.
And to provide an interpreter for the
intermediate language on each OS to translate the
binary code of the intermediate language into the
native binary code of the OS.
OS-Independent Compilation: Intermediate Language
Source Code for Language 1
Language 1 Compiler on OS1
Language 1 Compiler on OS2
Intermediate Binary Code
Intermediate Code Interpreter OS1
Intermediate Code Interpreter OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
Java Intermediate Language: Java Bytecode
Java Source Code (.java)
Java Compiler (javac) on OS1
Java Compiler (javac) on OS2
Java Bytecode (.class)
Java Interpreter on OS1 (java)
Java Interpreter on OS2 (java)
Binary Code for OS1
Binary Code for OS2
OS1
OS2
Program statements are interpreted one at a time during the run-time.
JIT Compiler
An interpreter interprets intermediate code one
line at a time. Slow execution.
A JIT (Just-In-Time) Compiler compiles the
complete code all at once just into native binary
code before execution. Faster execution.
JIT Complier: Java Bytecode Compiler
Java Source Code (.java)
Java Compiler (javac) on OS1
Java Compiler (javac) on OS2
Java Bytecode (.class)
Java JIT Compiler on OS1
Java JIT Compiler on OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
All programming statements are compiled at compile time.
MSIL: Microsoft Intermediate Language
Source Code for Language 1
Language 1 Compiler on OS1
Language 1 Compiler on OS2
MSIL Code
MSIL JIT Compiler on OS1
MSIL JIT Compiler on OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
.NET OS-Platform-Independence
JIT Compilation in .NET
All MSIL code are JIT-compiled to native binary
code before execution. No run-time interpretation,
faster execution.
A Common Language?
.NET Common Language Runtime
To make .NET language independent, CLR (Common Language
Runtime) is defined as the runtime environment.
CLR defines CTS (Common Type System) which should be
followed by all languages to be used in the .NET framework.
Syntax: int, for, ..
Semantics: multiple inheritance is not allowed in CTS
The code that follows CTS standard is called managed code.
regular C++ supports multiple inheritance
managed C++ does not support multiple inheritance
CLR: Common Language Runtime
Source Code for Language 1
Source Code for Language 2
Language 1 Compiler on OS1
Language 2 Compiler on OS2
MSIL Code Confirming CTS (Managed Code)
CLR on OS1
CLR on OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
.NET Language-Independence
.NET Architecture for Language and Platform Independence
(fan-in and fan-out on MSIL)
Source Code for Language 1
Source Code for Language 2
Language 1 Compiler on OS1
Language 2 Compiler on OS2
MSIL Code Confirming CTS (Managed Code)
CLR on OS1
CLR on OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
CLI (Common Language Infrastructure)
CLR/CTS for Everyone?
CLI : Common Language Infrastructure
A specification defines an environment for multiple
high-level languages to be used on different computer
platforms.
Created by Microsoft based on .NET, standardized by
MS, Intel, HP and others, ratified by ECMA and ISO.
.NET is an implementation of CLI for desktop systems.
.NET Compact Framework is an implementation of CLI
for portable devices.
Open Source implementations: Mono development
platform (Novell), Portable .NET (dotGNU)
CLI (Common Language Infrastructure) Specification
Open Architecture for Language and Platform Independent Programming
Source Code for Language 1
Source Code for Language 2
Language 1 Compiler on OS1
Language 2 Compiler on OS2
CIL (Common Intermediate Language) Code
Confirming CTS (Common Type System)
CLR for OS1
CLR for OS2
Binary Code for OS1
Binary Code for OS2
OS1
OS2
Even though, CLI/CTS/CLR can make a program
written in any language to run on any platform, the
entire program (including all libraries used) has to be
on the platform before running.
Can we have part of a program on one computer and
another part of the same program on another
computer?
Distributed Computing. A program is divided into
multiple parts and different parts are distribute on
different computers.
e.g. virtual surgery.
Web Enabled & Distributed
.Net is Web-enabled and Distributed
To run distributed code on the web, we need a
standard way to register the code and a standard
way to access the code.
Registration:
UDDI Registry: Universal Description,
Discovery, and Integration.
Access:
SOAP: Simple Object Access Protocol
WSDL: Web Service Description Language
.NET Architecture for Web-based Distributed Computing
Client 1
UDDI Registry 2
SOAP
Client 2
Web Service 1
UDDI Registry 1
WSDL Interface 1
Web Service 2
WEB
SOAP
WSDL Interface 2
Web Service Example
.NET Passport (one login for the whole Internet)
www.passport.com (run by Microsoft)
www.ubid.com (An online auction shop using
Passport web service)
Windows Live (one location to get all you need
from the Internet)
http://get.live.com/ (run by Microsoft)
Windows Live ID is replacing Passport ID.
.NET Framework Compositions
Common Language Runtime (CLR ): provides
the runtime environment for MSIL code.
.Net Framework Class Library (FCL) : provides
standard code for building common .Net
applications.
Classes in FCL are grouped into namespaces.
.Net Framework Class Library
System
Windows
Web
Data
(Database)
Forms
(GUI)
UI
Services
Enterprise
Services
XML
String,
(Data
Description)
…
Connection
DataSet
XmlDocument
.Net Framework Class Library
The most important groups are “the gang of four”:
• Windows Forms: for building GUIs for .Net
applications, language independent.
• ASP.NET: Active Server Pages for .Net, for
building web-accessible applications.
• ADO.NET: ActiveX Data Objects for .Net, for
accessing data in a database.
• Enterprise Services: for accessing COM+
services (transactions, object pooling).
.NET Application Types
Web Services
Browser
Local
Distributed
Accessible
Applications
Applications
Remote
Applications
.Net Framework Class Library
Common Language Runtime
OS
Other
Applications
.Net & COM
MFC: Microsoft Foundation Class, code reuse
within an application (process)
COM: Component Object Model, code reuse
across applications (processes)
DCOM: Distributed COM, code reuse across
systems
COM+: Internet-based Enterprise COM, code
reuse across the Internet
.NET: COM+ 2.0, all COM+ services are
available in .NET, even those not in managed
code, interoperable with COM-based applications
.NET My Services
Applications providing access to personal
information over the Internet.
• Passport (authentication)
• .NET Inbox (e-mail)
• .NET Documents (Internet-accessible storage)
• .NET Alerts (sending alert messages)
• .NET Calendar
• .NET Contacts
• .NET Wallet (payment inform)
• .NET List (to-do list)
.NET Enterprise Servers
Internet Information Services (IIS): web server
Commerce Server: e-commerce server
SQL Server: database server
Exchange Server: MS exchange services
Mobile Information Server: wireless server
Internet Security and Acceleration (ISA) Server:
firewall, proxy, …
BizTalk: B2B (Business-to-Business) server
A Common Language for the Internet
(free of compilation and translation)?
A Common Language for the Internet
•
•
•
•
Tim Berners-Lee
ASCII text (ISO/IEC 8859-1) is platform-independent.
HTTP (Hyper Text Transport Protocol)
e.g.
GET wp.html
Assembly Language for the Internet
HTML (Hyper Text Markup Language)
High-level language for the Internet)
hyper text: text that describes other text
tags: type definition of text in text
<title>WP</title>
all tags are predefined in HTML
only system defined types, no user defined types
Recognizable by all types of computers. (World Wide Web)
A Common Language for the Internet
XML (eXtensible Markup Language)
Allow user defined tags (types)
SOAP (Simple Object Access Protocol)
Standards for defining objects for the Internet
Based on XML
WSDL (Web Service Description Language)
Standards for describing web services for the Internet
Based on XML