C# 9.0 in a Nutshell: The Definitive Reference

1061 Pages·2021·10.54 MB·English

by  Joseph Albahari

C# 9.0
in a Nutshell
The Definitive Reference
Joseph Albahari

C# 9.0 IN A
NUTSHELL
THE DEFINITIVE REFERENCE
Joseph Albahari
C# 9.0 in a Nutshell
by Joseph Albahari
Copyright © 2021 Joseph Albahari. All rights reserved.
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978-1-098-10096-4
[LSI]
Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1. Introducing C# and .NET. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Object Orientation 1
Type Safety 2
Memory Management 3
Platform Support 3
CLRs, BCLs, and Runtimes 3
A Brief History of C# 8
2. C# Language Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
A First C# Program 25
Syntax 28
Type Basics 30
Numeric Types 41
Boolean Type and Operators 50
Strings and Characters 52
Arrays 54
Variables and Parameters 59
Expressions and Operators 70
Null Operators 74
Statements 76
Namespaces 87
3. Creating Types in C#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Classes 95
Inheritance 115
The object Type 125
iii
Structs 129
Access Modifiers 131
Interfaces 134
Enums 140
Nested Types 143
Generics 145
4. Advanced C#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Delegates 159
Events 167
Lambda Expressions 174
Anonymous Methods 179
try Statements and Exceptions 180
Enumeration and Iterators 189
Nullable Value Types 194
Nullable Reference Types 200
Extension Methods 202
Anonymous Types 204
Tuples 206
Records (C# 9) 210
Patterns 220
Attributes 225
Caller Info Attributes 227
Dynamic Binding 228
Operator Overloading 236
Unsafe Code and Pointers 240
Preprocessor Directives 245
XML Documentation 247
5. .NET Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
.NET Standard 254
Runtime and C# Language Versions 257
Reference Assemblies 257
The CLR and BCL 257
Application Layers 261
6. .NET Fundamentals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
String and Text Handling 265
Dates and Times 278
iv | Table of Contents
Dates and Time Zones 286
Formatting and Parsing 291
Standard Format Strings and Parsing Flags 297
Other Conversion Mechanisms 304
Globalization 308
Working with Numbers 309
Enums 313
The Guid Struct 317
Equality Comparison 317
Order Comparison 328
Utility Classes 331
7. Collections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Enumeration 337
The ICollection and IList Interfaces 345
The Array Class 349
Lists, Queues, Stacks, and Sets 357
Dictionaries 366
Customizable Collections and Proxies 372
Immutable Collections 378
Plugging in Equality and Order 382
8. LINQ Queries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 389
Getting Started 389
Fluent Syntax 391
Query Expressions 397
Deferred Execution 402
Subqueries 408
Composition Strategies 412
Projection Strategies 415
Interpreted Queries 417
EF Core 424
Building Query Expressions 435
9. LINQ Operators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
Overview 442
Filtering 445
Projecting 449
Joining 461
Table of Contents | v
Ordering 470
Grouping 472
Set Operators 476
Conversion Methods 477
Element Operators 480
Aggregation Methods 482
Quantifiers 486
Generation Methods 487
10. LINQ to XML. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 489
Architectural Overview 489
X-DOM Overview 490
Instantiating an X-DOM 494
Navigating and Querying 496
Updating an X-DOM 501
Working with Values 505
Documents and Declarations 507
Names and Namespaces 511
Annotations 516
Projecting into an X-DOM 517
11. Other XML and JSON Technologies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521
XmlReader 521
XmlWriter 529
Patterns for Using XmlReader/XmlWriter 531
Working with JSON 536
12. Disposal and Garbage Collection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 543
IDisposable, Dispose, and Close 543
Automatic Garbage Collection 549
Finalizers 551
How the GC Works 555
Managed Memory Leaks 562
Weak References 565
13. Diagnostics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
Conditional Compilation 571
Debug and Trace Classes 575
Debugger Integration 578
vi | Table of Contents
Processes and Process Threads 579
StackTrace and StackFrame 580
Windows Event Logs 582
Performance Counters 584
The Stopwatch Class 588
Cross-Platform Diagnostics Tools 589
14. Concurrency and Asynchrony. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595
Introduction 595
Threading 596
Tasks 612
Principles of Asynchrony 620
Asynchronous Functions in C# 625
Asynchronous Patterns 645
Obsolete Patterns 653
15. Streams and I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 657
Stream Architecture 657
Using Streams 659
Stream Adapters 673
Compression Streams 681
Working with ZIP Files 684
File and Directory Operations 685
File I/O in UWP 696
OS Security 700
Memory-Mapped Files 703
16. Networking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 707
Network Architecture 707
Addresses and Ports 709
URIs 710
Client-Side Classes 712
Working with HTTP 726
Writing an HTTP Server 730
Using FTP 733
Using DNS 735
Sending Mail with SmtpClient 735
Using TCP 736
Table of Contents | vii
Receiving POP3 Mail with TCP 740
TCP in UWP 742
17. Assemblies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 745
What’s in an Assembly 745
Strong Names and Assembly Signing 750
Assembly Names 751
Authenticode Signing 753
Resources and Satellite Assemblies 756
Loading, Resolving, and Isolating Assemblies 763
18. Reflection and Metadata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 785
Reflecting and Activating Types 786
Reflecting and Invoking Members 793
Reflecting Assemblies 805
Working with Attributes 806
Dynamic Code Generation 811
Emitting Assemblies and Types 818
Emitting Type Members 821
Emitting Generic Methods and Types 827
Awkward Emission Targets 829
Parsing IL 832
19. Dynamic Programming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 839
The Dynamic Language Runtime 839
Numeric Type Unification 840
Dynamic Member Overload Resolution 842
Implementing Dynamic Objects 848
Interoperating with Dynamic Languages 851
20. Cryptography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 855
Overview 855
Windows Data Protection 856
Hashing 857
Symmetric Encryption 859
Public-Key Encryption and Signing 864
21. Advanced Threading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 869
Synchronization Overview 870
viii | Table of Contents