Beginning C# and .NET. 2021 Edition

Cover....1

Title Page....7

Copyright Page....8

About The Authors....9

About The Technical Editor....11

Acknowledgments....13

Contents....15

Introduction....29

Who This Book is For....29

What This Book Covers....30

How This Book is Structured....31

The C# Language (Chapters 1–13)....31

Data Access (Chapters 14–17)....32

Additional Techniques (Chapters 18–21)....32

What You Need To Use This Book....33

Conventions....33

Source Code....34

ERRATA....35

Part I The C# Language....37

Chapter 1: Introducing C#....39

What Is .NET?....39

.NET Framework, .NET Standard, and .NET Core....40

Writing Programs Using .NET....41

CIL and JIT....41

Assemblies....42

Managed Code....43

Garbage Collection....43

Fitting It Together....43

Linking....44

What Is C#?....44

Applications You Can Write with C#....45

C# in This Book....46

Visual Studio....46

Visual Studio Products....46

Solutions....47

Chapter 2: Writing a C# Program....49

The Visual Studio Development Environment....50

Console Applications....54

The Solution Explorer....57

The Properties Window....58

The Error List Window....59

Desktop Applications....59

Chapter 3: Variables and Expressions....65

Basic C# Syntax....66

Basic C# Console Application Structure....69

Variables....70

Simple Types....70

Variable Naming....75

Literal Values....75

Binary Literals and Digit Separators....76

String Literals....77

Expressions....78

Mathematical Operators....79

Assignment Operators....84

Operator Precedence....85

Namespaces....86

Chapter 4: Flow Control....91

Boolean Logic....92

Boolean Bitwise and Assignment Operators....94

Operator Precedence Updated....96

Branching ....96

The Ternary Operator....97

The if Statement....97

Checking More Conditions Using if Statements....100

The switch Statement....101

Looping....104

do Loops....104

while Loops....107

for Loops....109

Interrupting Loops....110

Infinite Loops....111

Chapter 5: More about Variables....115

Type Conversion....116

Implicit Conversions....116

Explicit Conversions....118

Explicit Conversions Using the Convert Commands....120

Complex Variable Types....123

Enumerations....123

Defining Enumerations....124

Structs....127

Defining Structs....128

Arrays....130

Declaring Arrays....131

foreach Loops....134

Pattern Matching with switch case Expression....134

Multidimensional Arrays....138

Arrays of Arrays....140

String Manipulation....141

Chapter 6: Functions....149

Defining and Using Functions....150

Return Values....153

Parameters....154

Parameter Matching....157

Parameter Arrays....157

Reference and Value Parameters....159

Out Parameters....161

Tuples....162

Variable Scope....164

Variable Scope in Other Structures....167

Parameters and Return Values versus Global Data....168

Local Functions....170

The Main() Function....171

Struct Functions....173

Overloading Functions....174

Using Delegates....176

Chapter 7: Debugging and Error Handling....181

Debugging in Visual Studio....182

Debugging in Nonbreak (Normal) Mode....183

Outputting Debugging Information....184

Tracepoints....188

Diagnostics Output versus Tracepoints....190

Debugging in Break Mode....191

Entering Break Mode....191

Monitoring Variable Content....194

Stepping through Code....197

Immediate and Command Windows....198

The Call Stack Window....199

Error Handling....199

try. . .catch. . .finally....200

Throw Expressions....208

Listing and Configuring Exceptions....208

Chapter 8: Introduction to Object-Oriented Programming....211

What Is Object-Oriented Programming?....212

What Is an Object?....213

Properties and Fields....214

Methods....215

Everything’s an Object....216

The Life Cycle of an Object....216

Constructors....216

Destructors....217

Static and Instance Class Members....217

Static Constructors....217

Static Classes....218

OOP Techniques....218

Interfaces....218

Disposable Objects....220

Inheritance....220

Polymorphism....223

Interface Polymorphism....224

Relationships between Objects....225

Containment....225

Collections....226

Operator Overloading....227

Events....227

Reference Types versus Value Types....228

OOP in Desktop Applications....228

Chapter 9: Defining Classes....235

Class Definitions in C#....236

Interface Definitions....238

System.Object....241

Constructors and Destructors....243

Constructor Execution Sequence....245

OOP Tools in Visual Studio....248

The Class View Window....248

The Object Browser....250

Adding Classes....252

Class Diagrams....253

Class Library Projects....255

Interfaces versus Abstract Classes....259

Struct Types....261

Shallow Copying versus Deep Copying....263

Chapter 10: Defining Class Members....267

Member Definitions....268

Defining Fields....268

Defining Methods....269

Defining Properties....270

Tuple Deconstruction....275

Refactoring Members....276

Automatic Properties....277

Additional Class Member Topics....278

Hiding Base Class Methods....278

Calling Overridden or Hidden Base Class Methods....280

The this Keyword....280

Using Nested Type Definitions....281

Interface Implementation....283

Implementing Interfaces in Classes....284

Explicit Interface Member Implementation....285

Additional Property Accessors....285

Partial Class Definitions....286

Partial Method Definitions....287

Example Application....288

Planning the Application....289

The Card Class....289

The Deck Class....289

Writing the Class Library....289

Adding the Suit and Rank Enumerations....290

Adding the Card Class....292

Adding the Deck Class....294

A Client Application for the Class Library....297

The Call Hierarchy Window....298

Chapter 11: Collections, Comparisons, and Conversions....301

Collections....302

Using Collections....303

Defining Collections....308

Indexers....309

Adding a CardCollection to CardLib....311

Keyed Collections and IDictionary....314

Iterators....315

Iterators and Collections....320

Deep Copying....321

Adding Deep Copying to CardLib....322

Comparisons....324

Type Comparisons....324

Boxing and Unboxing....325

The is Operator....326

Pattern Matching with the is Operator Pattern Expression....329

Value Comparisons....330

Operator Overloading....330

Adding Operator Overloads to CardLib....335

The IComparable and IComparer Interfaces....340

Sorting Collections....342

Conversions....345

Overloading Conversion Operators....346

The as Operator....347

Chapter 12: Generics....351

What Are Generics?....352

Using Generics....353

Nullable Types....353

Operators and Nullable Types....354

The ?? Operator....355

The ?. Operator....356

Working with Nullable Types....357

The System.Collections.Generic Namespace....361

List....362

Sorting and Searching Generic Lists....363

Dictionary....369

Modifying CardLib to Use a Generic Collection Class ....370

Defining Generic Types....371

Defining Generic Classes....372

The default Keyword....374

Constraining Types....374

Inheriting from Generic Classes....380

Generic Operators....381

Generic Structs....382

Defining Generic Interfaces....382

Defining Generic Methods....382

Defining Generic Delegates....384

Variance....384

Covariance....385

Contravariance....386

Chapter 13: Additional C# Techniques....391

The :: Operator and the Global Namespace Qualifier....392

Custom Exceptions....393

Adding Custom Exceptions to CardLib....394

Events....395

What Is an Event?....395

Handling Events....397

Defining Events....399

Multipurpose Event Handlers....403

The EventHandler and Generic EventHandler Types....406

Return Values and Event Handlers....406

Anonymous Methods....406

Expanding and Using CardLib....407

Attributes....416

Reading Attributes....416

Creating Attributes....417

Initializers....418

Object Initializers....419

Collection Initializers....421

Type Inference....424

Anonymous Types....426

Dynamic Lookup....430

The dynamic Type....431

Advanced Method Parameters....435

Optional Parameters....435

Optional Parameter Values....436

The OptionalAttribute Attribute....436

Optional Parameter Order....437

Named Parameters....437

Lambda Expressions....441

Anonymous Methods Recap....441

Lambda Expressions for Anonymous Methods....443

Lambda Expression Parameters....446

Lambda Expression Statement Bodies....447

Lambda Expressions as Delegates and Expression Trees....448

Lambda Expressions and Collections....449

Part II Data Access....457

Chapter 14: Files....459

File Classes for Input and Output....460

The File and Directory Classes....460

The FileInfo Class....462

The DirectoryInfo Class....464

Path Names and Relative Paths....464

Streams....465

Classes for Using Streams....465

The FileStream Object....465

File Position....466

Reading Data....468

Writing Data....470

The StreamWriter Object....472

The StreamReader Object....475

Reading Data....476

Asynchronous File Access....477

Reading and Writing Compressed Files....478

Monitoring the File System....481

Chapter 15: XML AND JSON....489

XML Basics....490

JSON Basics....491

XML Schemas....491

XML Document Object Model....494

The XmlDocument Class....494

The XmlElement Class....495

Changing the Values of Nodes....499

Inserting New Nodes....501

Deleting Nodes....503

Selecting Nodes....505

Searching XML with XPath....505

JSON Serialization and Deserialization....509

Chapter 16: LINQ....515

LINQ to XML....516

LINQ to XML Functional Constructors....516

Working with XML Fragments....519

LINQ Providers....522

LINQ Query Syntax....522

Declaring a Variable for Results Using the var Keyword....524

Specifying the Data Source: from Clause....525

Specify Condition: where Clause....525

Selecting Items: select Clause....526

Finishing Up: Using the foreach Loop....526

Deferred Query Execution....526

LINQ Method Syntax....526

LINQ Extension Methods....527

Query Syntax versus Method Syntax....527

Lambda Expressions....528

Ordering Query Results....530

Understanding the orderby Clause....531

Querying a Large Data Set....532

Using Aggregate Operators....534

Using the Select Distinct Query....538

Ordering by Multiple Levels....540

Using Group Queries....542

Using Joins....544

Chapter 17: Databases....549

Using Databases....550

Entity Framework....550

Code- First versus Database- First....550

Migrations and Scaffolding....551

Install SQL Server Express LocalDB....551

A Code- First Database....552

Exploring Your Database....563

Navigating Database Relationships....566

Creating and Querying XML from an Existing Database....572

Part III Additional Techniques....579

Chapter 18: .NET and ASP.NET....581

Cross- Platform Basics and Key “Must Know” Terms ....583

What was .NET Standard? ....585

Shared Project, PCL, and .NET Standard....587

Building and Packaging a .NET Standard Library....589

Referencing and Targeting .NET....593

What was .NET Core?....594

Cross Platform....594

Open Source....595

Optimized for the Cloud....596

Performance....596

Modular Design....597

Self- Contained Deployment Model....598

Porting from .NET Framework to .NET....601

Identifying Third- Party Dependencies....603

Understanding Which Features Are Not Available....603

Upgrading the Current .NET Framework Target....603

Overview of Web Applications....604

Which ASP.NET to Use and Why....605

ASP.NET Web Forms....606

Server Controls....608

Input Validation....609

State Management....610

Authentication and Authorization....611

ASP.NET Web Site versus ASP.NET Web Applications....611

ASP.NET MVC/ASP.NET Core Web App MVC....613

ASP.NET Core Web API....615

ASP.NET Core Web App....616

IIS and Kestrel ....617

Blazor App and Razor Pages....618

Input Validation....620

State Management....621

Authentication and Authorization....622

Dependency Injection....622

Chapter 19: Basic Cloud Programming....627

The Cloud, Cloud Computing, and the Cloud Optimized Stack....628

Cloud Patterns and Best Practices....631

Using Microsoft Azure C# Libraries to Create a Storage Container....633

Creating an ASP.NET Core Web Application That Uses the Storage Container....643

Chapter 20: Basic Web API and WCF Programming....653

Creating an ASP.NET Core Web API....653

Consuming an ASP.NET Core Web API ....658

What Is REST?....665

What Is WCF?....666

WCF Concepts....667

WCF Communication Protocols....667

Addresses, Endpoints, and Bindings....668

Contracts....670

Message Patterns....670

Behaviors....671

Hosting....671

WCF Programming....671

The WCF Test Client....678

Defining WCF Service Contracts....680

Data Contracts....681

Service Contracts....681

Operation Contracts....682

Message Contracts....683

Fault Contracts....683

Self- Hosted WCF Services....688

Chapter 21: Basic Desktop Programming....699

XAML....700

Separation of Concerns....701

XAML in Action....701

Namespaces....702

Code- Behind Files....703

The Playground....703

WPF Controls....705

Properties....706

Dependency Properties ....709

Attached Properties....709

Events....710

Handling Events....711

Routed Events....712

Routed Commands....712

Control Types....715

Control Layout....715

Basic Layout Concepts....715

Stack Order....715

Alignment, Margins, Padding, and Dimensions....716

Border....716

Visual Debugging Tools....717

Layout Panels....718

Canvas....718

DockPanel....720

StackPanel....722

WrapPanel....723

Grid....724

The Game Client....727

The About Window....727

Designing the User Interface....728

The Image Control....728

The Label Control....728

The TextBlock Control....729

The Button Control....729

The Options Window....732

The TextBox Control....733

The CheckBox Control....734

The RadioButton Control....735

The ComboBox Control....736

The TabControl....737

Handling Events in the Options Window....741

Data Binding....743

The DataContext....744

Binding to Local Objects....744

Static Binding to External Objects....745

Dynamic Binding to External Objects....746

Starting a Game with the ListBox Control....748

Creating and Styling Controls....752

Styles....752

Templates....753

Triggers....755

Animations....756

WPF User Controls....757

Implementing Dependency Properties....758

The Main Window....772

The Menu Control....772

Routed Commands with Menus....772

Putting It All Together....777

Refactoring the Domain Model....777

The View Model....784

Completing the Game....793

Appendix: Exercise Solutions....805

Index....845

EULA....862

THE C# LANGUAGE WAS UNVEILED TO THE WORLD when Microsoft announced the first version of its .NET Framework in 2002. Since then, its popularity has rocketed, and it has arguably become the language of choice for desktop, web, cloud, and cross-platform developers who use .NET. Part of the appeal of C# comes from its clear syntax, which derives from C/C++ but simplifies some things that have previously discouraged some programmers. Despite this simplification, C# has retained the power of C++, and there is no reason now not to move into C#. The language is not difficult, and it is a great one with which to learn elementary programming techniques. This ease of learning combined with the capabilities of the .NET Framework make C# an excellent way to start your programming career.

The latest release of C# is C# 9 (included with.NET 5.0 and .NET Framework 4.8), which builds on the existing successes and adds even more attractive features. The latest releases of both Visual Studio and Visual Studio Code line of development tools also bring many tweaks and improvements to make your life easier and to dramatically increase your productivity.