C# Language
- Getting started with C# Language
- Learn Tutorial
- How to Start Learning C# While Still in College
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- .NET Compiler Platform (Roslyn)
- Access Modifiers
- Access network shared folder with username and password
- Accessing Databases
- Action Filters
- Aliases of built-in types
- An overview of c# collections
- Anonymous types
- Arrays
- ASP.NET Identity
- AssemblyInfo.cs Examples
- Async/await, Backgroundworker, Task and Thread Examples
- Async-Await
- Asynchronous Socket
- Attributes
- BackgroundWorker
- BigInteger
- Binary Serialization
-
BindingList
- Built-in Types
- C# 3.0 Features
- C# 4.0 Features
- Dynamic member lookup
- Optional parameters and named arguments
- Optional ref keyword when using COM
- Variance
- C# 5.0 Features
- C# 6.0 Features
- C# 7.0 Features
- C# Authentication handler
- C# Script
- Caching
- Casting
- Checked and Unchecked
- CLSCompliantAttribute
- Code Contracts
- Code Contracts and Assertions
- Collection Initializers
- Comments and regions
- Common String Operations
- Conditional Statements
- Constructors and Finalizers
- Creating a Console Application using a Plain-Text Editor and the C# Compiler (csc.exe)
- Creating Own MessageBox in Windows Form Application
- Creational Design Patterns
- Cryptography (System.Security.Cryptography)
- Data Annotation
- DateTime Methods
- Delegates
- Dependency Injection
- Diagnostics
- Dynamic type
- Enum
- Equality Operator
- Equals and GetHashCode
- Events
- Exception Handling
- Expression Trees
- Extension Methods
- File and Stream I/O
- FileSystemWatcher
- Func delegates
- Function with multiple return values
- Functional Programming
- Garbage Collector in .Net
- Generating Random Numbers in C#
- Generic Lambda Query Builder
- Generics
- Getting Started: Json with C#
- Guid
- Handling FormatException when converting string to other types
- Hash Functions
- How to use C# Structs to create a Union type (Similar to C Unions)
- ICloneable
- IComparable
- IDisposable interface
- IEnumerable
- ILGenerator
- Immutability
- Implementing Decorator Design Pattern
- Implementing Flyweight Design Pattern
- Import Google Contacts
- Including Font Resources
- Indexer
- Inheritance
- Initializing Properties
- INotifyPropertyChanged interface
- Interfaces
- Interoperability
- IQueryable interface
- Iterators
- Keywords
- Lambda expressions
- Lambda Expressions
- LINQ Queries
- Linq to Objects
- LINQ to XML
- Literals
- Lock Statement
- Looping
- Making a variable thread safe
- Methods
- Microsoft.Exchange.WebServices
- Named and Optional Arguments
- Named Arguments
- nameof Operator
- Naming Conventions
- Networking
- Nullable types
- Null-Coalescing Operator
- Null-conditional Operators
- NullReferenceException
- O(n) Algorithm for circular rotation of an array
- Object initializers
- Object Oriented Programming In C#
-
ObservableCollection
- Operators
- Overflow
- Overload Resolution
- Parallel LINQ (PLINQ)
- Partial class and methods
- Performing HTTP requests
- Pointers
- Pointers & Unsafe Code
- Polymorphism
- Preprocessor directives
- Properties
- Reactive Extensions (Rx)
- Read & Understand Stacktraces
- Reading and writing .zip files
- Recursion
- Reflection
- Regex Parsing
- Runtime Compile
- Singleton Implementation
- Static Classes
- Stopwatches
- Stream
- String Concatenate
- String Escape Sequences
- String Interpolation
- String Manipulation
- String.Format
- StringBuilder
- Structs
- Structural Design Patterns
- Synchronization Context in Async-Await
- System.DirectoryServices.Protocols.LdapConnection
- System.Management.Automation
- T4 Code Generation
- Task Parallel Library
- Task Parallel Library (TPL) Dataflow Constructs
- Threading
- Timers
- Tuples
- Type Conversion
- Unsafe Code in .NET
- Using Directive
- Using json.net
- Using SQLite in C#
- Using Statement
- Value type vs Reference type
- Verbatim Strings
- Windows Communication Foundation
- XDocument and the System.Xml.Linq namespace
- XML Documentation Comments
- XmlDocument and the System.Xml namespace
- Yield Keyword
C# Language C# 4.0 Features Variance
Example
Generic interfaces and delegates can have their type parameters marked as covariant or contravariant using the out and in keywords respectively. These declarations are then respected for type conversions, both implicit and explicit, and both compile time and run time.
For example, the existing interface IEnumerable<T> has been redefined as being covariant:
interface IEnumerable<out T>
{
IEnumerator<T> GetEnumerator();
}
The existing interface IComparer has been redefined as being contravariant:
public interface IComparer<in T>
{
int Compare(T x, T y);
}
