Chapter 15 Enumerated Types and Bit Flags 361

Enumerated Types....................................................................................... 361

Bit Flags........................................................................................................... 367

Adding Methods to Enumerated Types..................................................... 371

Chapter 16 Arrays 373

Initializing Array Elements........................................................................... 376

Casting Arrays............................................................................................... 378

All Arrays Are Implicitly Derived from System.Array........................... 380

All Arrays Implicitly Implement IEnumerable, ICollection,

and IList................................................................................................. 381

Passing and Returning Arrays.................................................................... 382

Creating Non-Zero Lower Bound Arrays.................................................. 383

Array Internals................................................................................................ 384

Unsafe Array Access and Fixed-Size Array.............................................. 388

Chapter 17 Delegates 391

A First Look at Delegates............................................................................. 391

Using Delegates to Call Back Static Methods.......................................... 394

Using Delegates to Call Back Instance Methods..................................... 395

Contents xiii

Demystifying Delegates............................................................................. 396

Using Delegates to Call Back Many Methods (Chaining)...................... 400

C#’s Support for Delegate Chains.................................................. 404

Having More Control over Delegate Chain Invocation................ 404

Enough with the Delegate Definitions Already (Generic Delegates).. 407

C#’s Syntactical Sugar for Delegates........................................................ 408

Syntactical Shortcut #1: No Need to Construct a

Delegate Object.................................................................................. 409

Syntactical Shortcut #2: No Need to Define a Callback Method

(Lambda Expressions)...................................................................... 410

Syntactical Shortcut #3: No Need to Wrap Local Variables

in a Class Manually to Pass Them to a Callback Method........... 413

Delegates and Reflection............................................................................ 416

Chapter 18 Custom Attributes 421

Using Custom Attributes.............................................................................. 421

Defining Your Own Attribute Class............................................................. 425

Attribute Constructor and Field/Property Data Types............................... 428

Detecting the Use of a Custom Attribute................................................... 430

Matching Two Attribute Instances Against Each Other........................... 434

Detecting the Use of a Custom Attribute Without Creating

Attribute-Derived Objects........................................................................ 437

Conditional Attribute Classes...................................................................... 440

Chapter 19 Nullable Value Types 441

C#’s Support for Nullable Value Types..................................................... 443

C#’s Null-Coalescing Operator................................................................... 446

The CLR Has Special Support for Nullable Value Types...................... 447

Boxing Nullable Value Types........................................................... 447

Unboxing Nullable Value Types...................................................... 448

Calling GetType via a Nullable Value Type.................................. 448

Calling Interface Methods via a Nullable Value Type.................. 448

Xiv Contents

PART IV CORE FACILITIES

Date: 2016-03-03; view: 804