List of Listings

Chapter 2. C# 2

Listing 2.1. Generating and printing names by using arrays

Listing 2.2. Generating and printing names by using ArrayList

Listing 2.3. Generating and printing names by using StringCollection

Listing 2.4. Generating and printing names with List<T>

Listing 2.5. Copying elements from one collection to another

Listing 2.6. Printing items in the invariant culture by using type constraints

Listing 2.7. Printing the result of the typeof operator

Listing 2.8. Exploring static fields in generic types

Listing 2.9. The effects of boxing nullable value type values

Listing 2.10. Calling GetType on nullable values leads to surprising results

Listing 2.11. A simple iterator yielding integers

Listing 2.12. The expansion of a foreach loop

Listing 2.13. Iterating over the Fibonacci sequence

Listing 2.14. An iterator that logs its progress

Listing 2.15. A simple foreach loop to iterate and log

Listing 2.16. Breaking out of a foreach loop by using an iterator

Listing 2.17. Expansion of listing 2.16 to not use a foreach loop

Listing 2.18. Reading lines from a file

Listing 2.19. Sample iterator method to decompile

Listing 2.20. Infrastructure of the generated code for an iterator

Listing 2.21. Simplified MoveNext() method

Listing 2.22. A simple partial class

Listing 2.23. Two partial methods—one implemented, one not

Listing 2.24. Demonstration of static classes

Listing 2.25. Namespace aliases in C# 1

Listing 2.26. Using fixed-size buffers for a versioned chunk of binary data

Chapter 3. C# 3: LINQ and everything that comes with it

Listing 3.1. Modeling an order in an e-commerce system

Listing 3.2. Creating and populating an order without object and collection initializers

Listing 3.3. Creating and populating an order with object and collection initializers

Listing 3.4. Modifying default headers on a new HttpClient with a nested object initializer

Listing 3.5. Anonymous type with Name and Score properties

Listing 3.6. Capturing variables in a lambda expression

Listing 3.7. Translation of a lambda expression with captured variables

Listing 3.8. Instantiating a local variable multiple times

Listing 3.9. Creating multiple context instances, one for each instantiation

Listing 3.10. Capturing variables from multiple scopes

Listing 3.11. Capturing variables from multiple scopes leads to multiple classes

Listing 3.12. A simple expression tree to add two integers

Listing 3.13. Handwritten code to create an expression tree to add two integers

Listing 3.14. Compiling an expression tree to a delegate and invoking the result

Listing 3.15. ToInstant extension method targeting DateTimeOffset from Noda Time

Listing 3.16. Invoking the ToInstant() extension method outside Noda Time

Listing 3.17. A simple query on strings

Listing 3.18. A simple query without using extension methods

Listing 3.19. A simple query in multiple statements

Listing 3.20. Introductory query expression with filtering, ordering, and projection

Listing 3.21. A let clause introducing a new range variable

Listing 3.22. Query translation using a transparent identifier

Chapter 4. C# 4: Improving interoperability

Listing 4.1. Taking a substring by using dynamic typing

Listing 4.2. Addition of dynamic values

Listing 4.3. Dynamic method overload resolution

Listing 4.4. Examples of compile-time failures involving dynamic values

Listing 4.5. Storing and retrieving items in an ExpandoObject

Listing 4.6. Using JSON data dynamically

Listing 4.7. Example of intended use of dynamic behavior

Listing 4.8. Implementing SimpleDynamicExample

Listing 4.9. The result of decompiling two simple dynamic operations

Listing 4.10. A LINQ query over a list of dynamic values

Listing 4.11. Attempting to call an extension method on a dynamic target

Listing 4.12. Attempting to use a dynamic element type in an IQueryable<T>

Listing 4.13. Dynamic access to a property of an anonymous type

Listing 4.14. Example of explicit interface implementation

Listing 4.15. Calling a method with optional parameters

Listing 4.16. Setting a range of values in Excel with implicit dynamic conversion

Listing 4.17. Creating a Word document and saving it before C# 4

Listing 4.18. Creating a Word document and saving it using C# 4

Listing 4.19. Accessing a named indexer

Listing 4.20. Creating a List<object> from a string query without variance

Listing 4.21. Creating a List<object> from a string query by using variance

Listing 4.22. Sorting a List<Circle> with an IComparer<Shape>

Chapter 5. Writing asynchronous code

Listing 5.1. Displaying a page length asynchronously

Listing 5.2. Retrieving a page length in an asynchronous method

Listing 5.3. Using unsafe code in an async method

Listing 5.4. Awaiting completed and noncompleted tasks

Listing 5.5. Catching exceptions when fetching web pages

Listing 5.6. Broken argument validation in an async method

Listing 5.7. Eager argument validation with a separate method

Listing 5.8. Creating a canceled task by throwing OperationCanceledException

Listing 5.9. Creating and calling an asynchronous function using a lambda expression

Listing 5.10. Wrapping a stream for efficient asynchronous byte-wise access

Listing 5.11. Skeleton of the members required for a generic task type

Listing 5.12. A simple async entry point

Chapter 6. Async implementation

Listing 6.1. Simple introductory async method

Listing 6.2. Generated code for listing 6.1 (except for MoveNext)

Listing 6.3. The decompiled MoveNext() method from listing 6.1

Listing 6.4. Pseudocode of a MoveNext() method

Listing 6.5. A section of listing 6.3 corresponding to a single await

Listing 6.6. Introducing a loop between await expressions

Listing 6.7. Awaiting in a loop

Listing 6.8. Decompiled loop without using any loop constructs

Listing 6.9. Awaiting within a try block

Listing 6.10. Decompiled await within try/finally

Listing 6.11. A sample custom task builder

Chapter 7. C# 5 bonus features

Listing 7.1. Capturing the iteration variable in a foreach loop

Listing 7.2. Capturing the iteration variable in a for loop

Listing 7.3. Basic demonstration of caller member attributes

Listing 7.4. Implementing INotifyPropertyChanged the old way

Listing 7.5. Using caller information to implement INotifyPropertyChanged

Listing 7.6. Caller information attributes and dynamic typing

Listing 7.7. Caller information in a constructor

Listing 7.8. Caller information in query expressions

Listing 7.9. Attribute class that captures caller information

Listing 7.10. Applying the attribute to a class and a method

Chapter 8. Super-sleek properties and expression-bodied members

Listing 8.1. Point class with public fields

Listing 8.2. Point class with properties in C# 1

Listing 8.3. Point class with properties in C# 3

Listing 8.4. Point class with read-only properties via manual implementation in C# 3

Listing 8.5. Point class with publicly read-only properties via automatic implementation with private setters in C# 3

Listing 8.6. Point class using read-only automatically implemented properties

Listing 8.7. Person class with manual property in C# 2

Listing 8.8. Person class with automatically implemented property in C# 3

Listing 8.9. Person class with automatically implemented read/write property in C# 6

Listing 8.10. Person class with automatically implemented read-only property in C# 6

Listing 8.11. Point struct in C# 5 using automatically implemented properties

Listing 8.12. Point struct in C# 6 using automatically implemented properties

Listing 8.13. Adding a DistanceFromOrigin property to Point

Listing 8.14. Delegating properties in Noda Time

Listing 8.15. Simple methods and operators in C# 5

Listing 8.16. Expression-bodied methods and operators in C# 6

Listing 8.17. IReadOnlyList<T> implementation using expression-bodied members

Listing 8.18. Extra expression-bodied members in C# 7

Chapter 9. Stringy features

Listing 9.1. Displaying a price, tip, and total with values aligned

Listing 9.2. Formatting a single date in every culture

Listing 9.3. Aligned values using interpolated string literals

Listing 9.4. Aligned values using a single interpolated verbatim string literal

Listing 9.5. Members declared by FormattableString

Listing 9.6. Formatting a date in the invariant culture

Listing 9.7. Awooga! Awooga! Do not use this code!

Listing 9.8. Safe SQL parameterization using FormattableString

Listing 9.9. Implementing safe SQL formatting

Listing 9.10. Implementing FormattableString from scratch

Listing 9.11. Even FormattableString evaluates expressions eagerly

Listing 9.12. Printing out the names of a class, method, field, and parameter

Listing 9.13. A simple method using its parameter twice in the body

Listing 9.14. Using nameof to raise a property change notification

Listing 9.15. Specifying a test case source with nameof

Listing 9.16. All the valid ways of accessing names of members in other types

Listing 9.17. Using an alias in the nameof operator

Chapter 10. A smörgåsbord of features for concise code

Listing 10.1. Polar-to-Cartesian conversion in C# 5

Listing 10.2. Polar-to-Cartesian conversion in C# 6

Listing 10.3. Selective importing of extension methods

Listing 10.4. Attempting to call Enumerable.Count in two ways

Listing 10.5. Using an indexer in a StringBuilder object initializer

Listing 10.6. Two ways of initializing a dictionary

Listing 10.7. A schemaless entity type with key properties

Listing 10.8. Two ways of initializing a SchemalessEntity

Listing 10.9. Exposing explicit interface implementations via extension methods

Listing 10.10. Adding a type-argument-specific Add method for dictionaries

Listing 10.11. Exposing explicit interface implementations via extension methods

Listing 10.12. Sketch of a null-conditional-friendly logging API

Listing 10.13. Throwing three exceptions and catching two of them

Listing 10.14. A three-level demonstration of exception filtering

Listing 10.15. A simple retry loop

Listing 10.16. Logging in a filter

Chapter 11. Composition using tuples

Listing 11.1. Representing the minimum and maximum values of a sequence as a tuple

Listing 11.2. Reading and writing tuple elements by name and position

Listing 11.3. Using a tuple instead of two local variables in MinMax

Listing 11.4. Reassigning the result tuple in one statement in MinMax

Listing 11.5. Implementing the Fibonacci sequence without tuples

Listing 11.6. Implementing the Fibonacci sequence with tuples

Listing 11.7. Separating concerns of sequence generation for Fibonacci

Listing 11.8. Equality and inequality operators

Listing 11.9. Finding and ordering distinct points

Listing 11.10. Structural comparisons with a case-insensitive comparer

Listing 11.11. Displaying the highest-scoring player for a date

Listing 11.12. A refactoring to use a tuple local variable

Chapter 12. Deconstruction and pattern matching

Listing 12.1. Overview of deconstruction using tuples

Listing 12.2. Calling a method and deconstructing the result into three variables

Listing 12.3. Assignments to existing variables using deconstruction

Listing 12.4. Simple constructor assignments using deconstruction and a tuple literal

Listing 12.5. Deconstruction in which evaluation order matters

Listing 12.6. Slow-motion deconstruction to show evaluation order

Listing 12.7. Deconstructing a Point to two variables

Listing 12.8. Using an extension method to deconstruct DateTime

Listing 12.9. Using Deconstruct overloads

Listing 12.10. Computing a perimeter without patterns

Listing 12.11. Computing a perimeter with patterns

Listing 12.12. Simple constant matches

Listing 12.13. Using type patterns instead of as/if

Listing 12.14. Behavior of nullable value types in type patterns

Listing 12.15. Generic method using type patterns

Listing 12.16. Using the var pattern to introduce a variable on error

Listing 12.17. Implementing the Fibonacci sequence recursively with patterns

Listing 12.18. Using multiple case labels with patterns for a single case body

Chapter 13. Improving efficiency with more pass by reference

Listing 13.1. Using the same variable for multiple ref parameters

Listing 13.2. Incrementing twice via two variables

Listing 13.3. Modifying array elements using ref local

Listing 13.4. Aliasing the field of a specific object by using ref local

Listing 13.5. Identity conversion in ref local declaration

Listing 13.6. Simplest possible ref return demonstration

Listing 13.7. Incrementing the result of a ref return directly

Listing 13.8. A ref return indexer exposing array elements

Listing 13.9. Counting even and odd elements in a sequence

Listing 13.10. ref readonly return and local

Listing 13.11. A read-only view over an array with copy-free reads

Listing 13.12. Valid and invalid possibilities for passing arguments for in parameters

Listing 13.13. in parameter and value parameter differences in the face of side effects

Listing 13.14. Using in parameters safely

Listing 13.15. A trivial year/month/day struct

Listing 13.16. Accessing properties via a read-only or read-write field

Listing 13.17. A trivial Vector3D struct

Listing 13.18. Extension methods using ref and in

Listing 13.19. Calling ref and in extension methods

Listing 13.20. Generating a random string by using a char[]

Listing 13.21. Generating a random string by using stackalloc and a pointer

Listing 13.22. Generating a random string by using stackalloc and a Span<char>

Listing 13.23. Generating a random string with string.Create

Chapter 14. Concise code in C# 7

Listing 14.1. A simple local method that accesses a local variable

Listing 14.2. Local method modifying a local variable

Listing 14.3. What Roslyn does with listing 14.2

Listing 14.4. Capturing variables from multiple scopes

Listing 14.5. What Roslyn does with listing 14.4

Listing 14.6. Method group conversion of a local method

Listing 14.7. What Roslyn does with listing 14.6

Listing 14.8. Implementing Select without local methods

Listing 14.9. Implementing Select with a local method

Listing 14.10. Using an out variable in a constructor initializer

Listing 14.11. Specifying a default literal as a method argument

Listing 14.12. New constraints in C# 7.3

Chapter 15. C# 8 and beyond

Listing 15.1. Initial model before C# 8

Listing 15.2. Model with non-nullable properties everywhere

Listing 15.3. Making the customer Address property nullable

Listing 15.4. Safe dereferencing using the null conditional operator

Listing 15.5. Checking a reference with a local variable

Listing 15.6. Checking a reference with repeated property access

Listing 15.7. Using the bang operator to satisfy the compiler

Listing 15.8. Using the bang operator in unit tests

Listing 15.9. Converting a switch statement into a switch expression

Listing 15.10. Using a switch expression to implement an expression-bodied method

Listing 15.11. Matching nested patterns

Listing 15.12. Matching customers against multiple patterns concisely

Listing 15.13. Trimming the first and last character from a string with a range

Listing 15.14. Index and range literals

Listing 15.15. Using indexer overloads for index and range in a string and a span

Listing 15.16. Implementing IAsyncDisposal and calling it with using await

Listing 15.17. Simplified RPC-based service for listing cities

Listing 15.18. Wrapper around the RPC service to provide a simpler API

Listing 15.19. Using foreach await with a GeoClient

Listing 15.20. Implementing ListCitiesAsync with an iterator