Sams microsoft visual c sharp 2005 unleashed may 2006 ISBN 0672327767

Since then, he has dedicated himself to learning all there is to know about programming, and using every programming language he couldfind, including Pascal, C, C++, Scheme, LISP, ADA, P

By Kevin Hoffman

Publisher: Sams Pub Date: May 09, 2006 Print ISBN-10: 0-672-32776-7 Print ISBN-13: 978-0-672-32776-6 Pages: 720

Table of Contents | Index

Setting the standard for a premium C# reference, Microsoft Visual C# 2005 Unleashed

provides practical examples for virtually every aspect of the C# programming language The book is structured for progressive learning, so it can be read cover-to-cover or used as

a comprehensive reference guide You will be exposed to everything from low-level

information on the Garbage Collector to advanced concepts, such as creating applications that use Enterprise Services, creating Web Services, and even advanced Windows GUI Chapters include:

By Kevin Hoffman

Publisher: Sams Pub Date: May 09, 2006 Print ISBN-10: 0-672-32776-7 Print ISBN-13: 978-0-672-32776-6 Pages: 720

Microsoft® Visual C# 2005 Unleashed

Copyright © 2006 by Sams Publishing

All rights reserved No part of this book shall be reproduced,stored in a retrieval system, or transmitted by any means,

electronic, mechanical, photocopying, recording, or otherwise,without written permission from the publisher No patent

liability is assumed with respect to the use of the informationcontained herein Although every precaution has been taken inthe preparation of this book, the publisher and author assume

no responsibility for errors or omissions Nor is any liabilityassumed for damages resulting from the use of the informationcontained herein

regarded as affecting the validity of any trademark or servicemark

Microsoft is a registered trademark of Microsoft Corporation

Every effort has been made to make this book as complete and

as accurate as possible, but no warranty or fitness is implied.The information provided is on an "as is" basis The author andthe publisher shall have neither liability nor responsibility to anyperson or entity with respect to any loss or damages arisingfrom the information contained in this book

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Regardless of where the inspiration comes from or what it produces, it's still a highly creative process that is subject to writer's block and fits of irritability, crankiness, defeatism, and being so absorbed in a particular topic that the world around

It truly is a battle, "me vs the technology." The problem is that this battle requires a huge time investment Somehow my wife has managed to tolerate me being in the same room but simply

"not being there" while I type away in order to defeat the

chapters that loom before me, daring me to take them on My daughter, Jerrah, has her own keyboard so that she can

pretend to "be busy" just like Daddy There's something

bittersweet about the fact that she wants to be like me, but that her impression of me is one of being busy and typing all the time.

My wife's patience, love, caring, and support have been

invaluable Without her support, I would've given up on writing before I even got started And certainly without her I never

would have been able to write this book, the single largest and most time-consuming book I've ever written.

Regardless of which deity you believe in, or whether you believe

in one, you must concede the existence of angels After all, I

am married to one.

Kevin Hoffman has been programming for more than 20

years He got started when his grandfather repaired a discardedCommodore VIC-20 and he got right to work creating text-

based role-playing games in BASIC Since then, he has

dedicated himself to learning all there is to know about

programming, and using every programming language he couldfind, including Pascal, C, C++, Scheme, LISP, ADA, Perl,

Python, Java, and many others When he first saw a pre-betarelease of C# 1.0, he was hooked He knew at that momentthat the NET Framework would revolutionize how developerscreated software and how people designed software, and wouldenable new types of applications and new functionality that

either used to be impossible or too cost-prohibitive to even

attempt As a result of his passion for the NET Framework, hehas dubbed himself the ".NET Addict."

As the reader of this book, you are our most important critic

and commentator We value your opinion and want to know

what we're doing right, what we could do better, what areasyou'd like to see us publish in, and any other words of wisdomyou're willing to pass our way

As a publisher for Sams Publishing, I welcome your comments.You can email or write me directly to let me know what you did

or didn't like about this bookas well as what we can do to makeour books better

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If you can force yourself to think back 10 years, think about theproliferation of technology in just that short period of time

Back in the "good ole" days, you could walk down a busy citystreet, and you probably wouldn't see anyone talking on a cellphone You wouldn't see people busily tapping at their PDAs.You definitely didn't see anyone sitting in an Internet café using

a Tablet PC to send hand-sketched application designs halfwayaround the world to a remote development team

Connectivity between applications and application componentsused to be something that required the use of extremely skilled,highly expensive development efforts Sure, we had

technologies like CORBA, but they had limited use

Today, connectivity itself has become so ubiquitous that it is

demanded When people turn on their PDA in an Internet-enabled coffee shop, they fully expect that they will be able toconnect to the Internet from there If they don'tthey will

complain to the owner When people flip open their brand newcellular phone, not only do they expect it to take photographs,but they expect to be able to upload their photos to a centrallocation to be shared with friends, family, or the entire Internet.They expect that they can download ringtones, games, evenmusic and videos If they can'tthey want their money back

This same demand for connectivity, performance, and modernfeatures can be found in desktop software and web software aswell People want their applications to follow the "It Just Works"principle They should be able to beat on and otherwise abusethat application without fear of retribution in the form of lost orcorrupted data Users want their Windows applications to workproperly whether they're connected to the Internet or not Theywant their web applications to be more responsive than theyused to be, they want them to look great, and they want them

In short, the demands modern users are placing on the quality,features, and functionality of the applications they use havenever been more strict Programmers today must create some

of the most powerful applications ever written, and they need to

do it quickly, reliably, and cheaply

This book will take the developer through an in-depth

exploration of the features, power, and capabilities of Visual C#.NET 2005, the latest and most powerful version of the C#

language running on the NET Framework 2.0

Among many other things, by reading this book you will

Learn the fundamentals of the C# language and the corefeatures of the NET Framework 2.0, such as object-

oriented programming, generics, and other basics such asdelegates and event-driven programming

Use remoting and/or COM+ to create distributed, connectedapplications

This book is crammed full of information on how to get you up

to speed on the newest technology It also provides you withpractical application of the technology As we all know, applying

a technology just because it's new or interesting isn't

necessarily the right thing to do As you read this book, you will

be introduced to the new technology from the ground up

(learning to walk before you can run), as well as learning wherethat technology makes sense and when it should be applied

However, many of the later chapters in the book build on

technologies and techniques introduced in earlier chapters,

making this book ideally suited to being read from start to

finish

If you already have a working knowledge of the C# languagefrom your experience with previous versions (either 1.0 or 1.1),you can skip this chapter and move on Take care not to skiptoo many of the early chapters, as there have been

enhancements to the language that are covered early on in thebook, such as generics and anonymous methods This chapteralso skips over some details that you may not be aware of ifyou have very little exposure to programming If you have

never written software on the Windows platform (either

Windows or Web-based), this is the wrong chapter, and perhapsthe wrong book, for you

Before you learn the mechanics of the C# language itself, it isimportant that you learn the evolution of technologies that

created the need for a language like C# This section takes you

on a quick tour of the history of C#, followed by an explanation

of the Common Language Runtime, the Common Type System,and concluding with an overview of garbage-collected

environments

The Evolution of NET

Before the NET Framework was released to the public, the

majority of component-oriented development for the Windowsplatform took the form of COM objects Component Object

Model (COM), a binary standard for creating reusable

components, allowed developers to write code that solved

smaller problems in smaller problem domains By breaking

down the problem into components, the solution often becameeasier and the components used to solve the problem could bereused to solve other similar problems

COM offered many advantages and disadvantages One of themost common problems with the COM standard was

appropriately dubbed "DLL hell." DLL hell arose when COM

interfaces were indexed in the registry and then newer versions

of those components were released Versioning often causeddevelopers headaches due to the tightly coupled, binary nature

of the standard In addition, if a DLL's location changed on thefile system without the information in the registry being

modified, the COM interfaces contained within that DLL wouldbecome inaccessible You could see examples of this when anew application was installed with a different version of someshared component, and it would not only break the new

Other problems with development at the time included thingslike difficulty managing memory, slow development times, GUIcontrols that were typically insufficient for many tasks, as well

as a lack of interoperability between languages such as C++and Visual Basic

As a solution to this and countless other problems with

development at the time, Microsoft began working on what was

then referred to as COM+ 2.0 The solution would provide a

managed environment in which code would be executed thatwould provide for enhanced type safety, security, and an

incredibly extensive library of useful classes and functions tomake the lives of developers much easier Eventually this

solution became what is now the NET Framework Versions 1.0and 1.1 have been released and now version 2.0 is available Inthe next few sections, some of the key aspects of the NET

Framework will be discussed: the Common Language Runtime,the Common Type System, and the concept of garbage-

collected managed code

The Common Language Runtime

Before talking about the basics of C#, you need to know a littlebit about how C# (and all other NET languages) works and

where it sits in relation to the various components that makethe entire NET Framework run

One such component is the Common Language Runtime (almost

exclusively referred to as the CLR) Unlike previous versions ofC++ and similar languages, C# runs in a managed

environment Code that you write in C# runs inside the context

of the Common Language Runtime The runtime is responsiblefor managing things like memory and security and isolating

Library The BCL (Base Class Library) is the collection of classesand utilities written in the NET Framework that provide youwith the fundamentals you need in order to create your

applications, such as code to allow you to deal with encryption,data access, file I/O, web applications, Windows applications,and much more As you will see throughout the book, much ofthe task of learning C# isn't learning the language syntax; it'slearning about the vast library of the BCL In short, the CLR isthe managed execution engine that drives the code written inthe BCL and any applications you create

Don Box has written an excellent book on the Common

Language Runtime that gives all the detail you can possibly

imagine on what the CLR is and how it works The book is called

Essential NET Volume I: The Common Language Runtime

The Common Type System

A common problem in many programming languages is the

inability to exchange data between programs written in differentlanguages For example, you have to take special precautionswhen invoking C methods from Pascal, and Pascal methods

from C because of parameter ordering In addition, strings in Cconsist of an array of characters that are terminated with theASCII NULL (typically represented as \0) In Pascal, the firstbyte of a string actually contains the length of the string Theseproblems are just the tip of the iceberg As you can tell, gettingdifferent languages to communicate with each other can be anightmarish task (and, historically, it has been)

languages creates an environment where VB.NET and C# codecan coexist side by side without any communication issues

Taking Out the Trash: Coding in a Garbage-Collected Environment

As I mentioned earlier in this section, the CLR does quite a bit

of memory management on your behalf If you have used C#1.0 or 1.1, you will be familiar with this concept One of the

components of the CLR is the Garbage Collector When you

collection cycle takes place, the Garbage Collector examinesyour variables and if they are no longer in use, it will dispose of

them (referred to as a collection) In Chapter 16, "Optimizingyour NET 2.0 Code," you will learn more about the GarbageCollector (GC) and how awareness of its presence while codingand designing can improve the speed of your applications Fornow, it is good enough to know that the GC is there managingyour memory and cleaning up after you and your variables

My favorite analogy for explaining variables is the "bucket"

analogy Think of a variable as a bucket Into that bucket, youcan place data Some buckets don't care what kind of data youplace in them, and other buckets have specific requirements onthe type of data you can place in them You can move data fromone bucket to another Unfortunately, the bucket analogy gets alittle confusing when you take into account that one bucket cancontain a little note inside that reads "see Bucket B for actualdata" (you'll read about reference types shortly in the section

"Value Types vs Reference Types")

To declare a variable in C#, you can use the following syntax:type variable_name;

virtually unlimited

Table 1.1 Core NET Data Types Data Type Description

organizes all types into namespaces A namespace is a logical

container that provides name distinction for data types Thesecore data types all exist in the "System" namespace You'll seemore namespaces throughout the book as you learn aboutmore specific aspects of NET

Type Shortcuts

C# provides you with some shortcuts to make declaring some

word lowercase aliases that, when compiled, will still represent

of the core data types easier These shortcuts are simple one-a core NET type Table 1.2 lists some data type shortcuts andtheir corresponding NET types

experience) the actual data contained in the heap Reference

types are generally larger and slower than value types Learningwhen to use a reference type and when to use a value type issomething that comes with practice and experience

You will learn a lot of C# syntax tricks as you progress throughthe book This section introduces you to the most basic

concepts required to create the simplest C# applicationthe

canonical "Hello World" sample

Code Blocks

As you know, all programming languages work on the samebasic principle: individual instructions are executed in sequence

to produce some result Instructions can be anything from

defining a class to printing information to the Console output

In C#, multiple lines of code are grouped together into a logicalexecution block by wrapping the lines of code with the "curlybrackets" or braces: the { and } symbols

The Canonical "Hello World" Sample

It seems as though virtually every book on a programming

language starts off with a program that prints the phrase "HelloWorld" to the console Rather than risk horrible karma and

unknown repercussions from breaking with tradition, I am going

to inflict my own version of "Hello World" upon you

To start, open up whatever 2005 IDE you have (C# Express

2005, or any of the Visual Studio 2005 editions) and create anew Console Application (make sure you select C# if you havemultiple languages installed) called HelloWorld Make sure thatyour code looks the same as the code shown in Listing 1.1

Web applications Create amazingly powerful, rich, full-featured web applications in the shortest amount of timeever, taking advantage of new features like Web Parts,

Mobile applications Create web applications that

automatically recognize mobile platforms and adapt to thesmall form factor and limited capacity of PocketPCs andcellular phones

Mobile clients Create applications that target the PocketPCplatform and can not only communicate with other desktopapplications, but can also communicate with the Internet,consume web services, and interact with SQL databases

productivity, performance, and reliability

Integration applications Take advantage of COM

Interoperability as well as NET-based APIs to integrate yourown code with other applications such as Office 2003,

SharePoint Portal Server 2003, and much, much more

This chapter provided you with a brief introduction to the world

of the NET Framework and C# 2.0 You read about how the.NET Framework evolved as well as what it is now In addition,you were introduced to the Common Language Runtime, theGarbage Collector, the Common Type System, and finally a verysmall introductory application

This chapter has provided you with the basic foundation thatyou will need in order to continue learning about C# 2005 byprogressing through this book

of how to accomplish both of these types of tasks using the C#language

If you have any familiarity with programming languages at all,the concepts discussed in this chapter should seem familiar andwill be easy for you to pick up the C# syntax If you have

already been using C# for some time, you should be able toskim this chapter briefly as a refresher before continuing onthrough the rest of the book

Every modern programming language supports the notion ofbranching and conditional logic This gives your applications theability to do different things based on current input, events,error conditions, or any condition that can be expressed

logically This section first shows you how C# allows you to formlogical expressions and how to create code blocks that are

executed conditionally based on those expressions Then you'llsee a couple of shortcuts and extras that C# contains to makeusing certain types of common logic statements even easier

Introduction to Boolean Expressions

A Boolean expression is a code statement that will eventuallyevaluate to either true or false At the most basic level, all

Boolean expressions, no matter how long or complex, are stillgoing to evaluate to either true or false

The simplest of all Boolean expressions is equality This

expression is used to test whether or not one value is

equivalent to another value This can be something simple, suchas

2 == 4

This expression will evaluate to false because 2 is not equal to

4 It can also be something complex, such as

MyObject.MyProperty == YourObject.YourProperty