Introduction to Microsoft Dot Net Framework and Custom ...ctchen/pdf/ITMDFACA.pdf · Introduction to Microsoft Dot Net Framework and Custom Attributes 뎯ꯘꟸ 2003/03/13 ctchen@ctchen.idv.tw

Introduction to Microsoft Dot Net Framework and

Custom Attributes

陳建村

2003/03/13ctchen@ctchen.idv.tw

References

J. Newkirk & A. A. Vorontsov, “How .NET’s Custom Attributes Affect Design”, IEEE Software, Sep/Oct 2002.Bertrand Meyer, “.NET is Coming, ” IEEE Computer, August 2001.J. Liberty, Programming C#, O’Reilly, 2002.J. Liberty & D. Hurwitz, Programming ASP.NET, O’Reilly, 2002.J. Richter, Applied Microsoft .NET Framework Programming, MS Press, 2002.

Outline

.NET Platform OverviewCustom Attributes & Their Applications

BugFixAttributeDesign By ContractWeb ServicesConditionalAttributeNUnit 2.0

Conclusion

Part I: .NET Platform Overview

Features of the .NET Platform (1/2)

Multi-language developmentC#, C++, VB.NET, JScript, J#, Eiffel, Perl, ML, etc.

Platform and processor independenceMicrosoft Intermediate Language (MSIL)

Automatic memory managementGarbage Collection (GC)

Version supportNo more “DLL Hell”

Support for open standardsSOAP, UDDI, WSDL, XML, ECMA standards, etc.

Features of the .NET Platform (2/2)

Easy deploymentXcopy deployment, and no registry

Distributed architectureWeb services

Interoperability with unmanaged codeCalling DLL function, using COM components, and calling .NET services from COM components

SecurityPerformance and Scalability

Microsoft.NET Framework

Base Class Library

Common Language Specification

Common Language Runtime (CLR)

Data and XML

VB C++ C#Visual Studio.N

ETJScript …

WebServices

UserInterface

The .NET Architecture (Meyer)

2-1

3-1

2-2

2-3

1

2

3

4

5

6

Web services

The top layer provides .NET users-persons and companies-with Web services for e-commerce and business-to-business applications.

Frameworks and libraries

A set of frameworks and libraries provides the most immediately attractive aspect for developers. These include ASP.NET, active server pages for developing smart Web sites and services; ADO.NET, and XML-based improvement to ActiveX Data Objects, for databases and object-relational processing; and Windows Forms for graphics. Altogether, .NET contains thousands of reusable components.

Development environment

The new Visual Studio.Net provides the tools of most direct use to developers: A common software development, compilation, browsing, and debugging shared by many languages. This environment allows third-party vendors to plug in tools and compilers for other languages.

Component model

Before .NET there were already three major contenders for leadership in the field of models and standards for component: CORBA, J2EE and COM.With .NET you can build assemblies, each consisting of a number of classes with well-defined interfaces.

Component model (2/2)ILDASM

Object model

The object model provides the conceptual basis on which everything else rests, in particular, .NET's OO type system. The common language specification defines restrictions ensuring language operability.

Common language runtime

A

Basic class library

Visual Studio.Net

Visual Studio.Net- new project

Visual Studio.Net- Win App. (1/3)

B

A

Visual Studio.Net- Win App. (2/3)

Visual Studio.Net- Win App. (3/3)

ASP.NET

Web controlsServer side web controlsAutomatically state maintenance

View stateSession state

Compiled approachClosing the gap (web form)

With .NET, a Web page is a program, and a program can easily become a Web page

Demo

ASP.NET- Demo

ASP.NET- Demo

ASP.NET- Demo

ASP.NET- Demo

Security

Type verificationOrigin verificationA fine-grained permission mechanismA notion of "principal"

Beyond Windows

The open source project- Mono:http://www.go-mono.comLasted version: 0.23 (2003/03/07)

Mono includes: a compiler for the C# language, a runtime for the Common Language Infrastructure (also referred as the CLR) and a set of class libraries. The runtime can be embedded into your application.

Mono has implementations of both ADO.NET and ASP.NET as part of its distribution.

Part II: Custom Attributes

What is Custom Attributes?

Attributes, such as public, private, staticcan be applied to types and members.How about defining our own attributes?Custom attributes is a way to associate additional information with a target.

The complier detects the attributes in the source code and emits the corresponding metadata.

Custom attributes example-in C#

Custom attributes example-in VB.Net

Custom attributes’s targetsAllAssemblyClassConstructorDelegateEnumEventField

InterfaceMethodModuleParameterPropertyReturn ValueStruct

The System.Attribute class

A custom attribute is simply an instance of a type. Custom attribute types must derived from System.Attribute class (directly or indirectly)The type must have a public constructor to create an instance of it. When applying an attribute to a target, the syntax is similar to that for calling one of the type’s instance constructors.

Example- BugFixAttribute

Real example- BugFixAttribute

MyMath

Tester

Output

Example- Design By Contract

DBC in Eiffel

precondition

postcondition

DBC in Java (iContract)

DBC in .NET platform (1/2)

DBC in .NET platform (2/2)

Example- Web Services

A Simple StockTicker

The StockTicker web service exposes two web methods:

GetNameExpects a stock symbol as an argument and returns a string containing the name of the stock.

GetPriceExpects a stock symbol as an argument and returns a number containing the current price of the stock.

Source Code (1/2)

Source Code (2/2)

Two web methods

The WebMethod attribute

It’s not necessary for the WebService class to expose all of its methods to consumers of the web service. Each method we want to expose must:

Be declared as public.Have the WebMethod attribute placed before the method declaration.

Invoke GetName (1/2)

Invoke GetName (2/2)

Invoke GetPrice (1/2)

Invoke GetPrice (2/2)

StockTicker’s WSDL

Example- ConditionalAttribute

Demo ConditionalAttribute

Output

Specifying a preprocessor symbol in VS.NET

Output

Example- NUnit 2.0

JUnit review

Custom attributes in NUnit 2.0

Conclusion

We now understand the major features of the .NET platform.JSR 175- A Metadata Facility for the Java Programming Language:

A metadata facility for the Java Programming Language would allow classes, interfaces, fields, and methods to be marked as having particular attributes.http://www.jcp.org/en/jsr/detail?id=175

Q&A

The .NET program execution modelMulti-language

Platform independence

Automatic memory management

*

Common Language Runtime (CLR)