Tutorial by Examples: p

HttpClient is available through NuGet: Microsoft HTTP Client Libraries. string requestUri = "http://www.example.com"; string requestBodyString = "Request body string."; string contentType = "text/plain"; string requestMethod = "POST"; var request = new ...

Code can and should throw exceptions in exceptional circumstances. Examples of this include: Attempting to read past the end of a stream Not having necessary permissions to access a file Attempting to perform an invalid operation, such as dividing by zero A timeout occurring when downloading a...

var persons = new[] { new {Id = 1, Name = "Foo"}, new {Id = 2, Name = "Bar"}, new {Id = 3, Name = "Fizz"}, new {Id = 4, Name = "Buzz"} }; var names = persons.Select(p => p.Name); Console.WriteLine(string.Join(",", names....

var numbers = new[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }; var evenNumbersBetweenSixAndFourteen = new[] { 6, 8, 10, 12 }; var result = numbers.Except(evenNumbersBetweenSixAndFourteen); Console.WriteLine(string.Join(",", result)); //1, 2, 3, 4, 5, 7, 9

Enumerable.Select returns an output element for every input element. Whereas Enumerable.SelectMany produces a variable number of output elements for each input element. This means that the output sequence may contain more or fewer elements than were in the input sequence. Lambda expressions passe...

Skip will enumerate the first N items without returning them. Once item number N+1 is reached, Skip starts returning every enumerated item: var numbers = new[] {1,2,3,4,5}; var allNumbersExceptFirstTwo = numbers.Skip(2); Console.WriteLine(string.Join(",", allNumbersExceptFirstTwo.ToA...

var mixed = new object[] {1,"Foo",2,"Bar",3,"Fizz",4,"Buzz"}; var numbers = mixed.OfType<int>(); Console.WriteLine(string.Join(",", numbers.ToArray())); //1,2,3,4

.NET4.0 var tens = new[] {10,20,30,40,50}; var units = new[] {1,2,3,4,5}; var sums = tens.Zip(units, (first, second) => first + second); Console.WriteLine(string.Join(",", sums)); //11,22,33,44,55

var persons = new[] { new { Name="Fizz", Job="Developer"}, new { Name="Buzz", Job="Developer"}, new { Name="Foo", Job="Astronaut"}, new { Name="Bar", Job="Astronaut"}, }; var groupedByJob = person...

var numbers = new[] {2,4,6,8,1,3,5,7}; var oddNumbers = numbers.SkipWhile(n => (n & 1) == 0); Console.WriteLine(string.Join(",", oddNumbers.ToArray())); //1,3,5,7

var numbers = new[] {2,4,6,8,1,3,5,7}; var numbersOrDefault = numbers.DefaultIfEmpty(); Console.WriteLine(numbers.SequenceEqual(numbersOrDefault)); //True var noNumbers = new int[0]; var noNumbersOrDefault = noNumbers.DefaultIfEmpty(); Console.WriteLine(noNumbersOrDefault.Count()); //1 C...

var persons = new[] { new { Name="Fizz", Job="Developer"}, new { Name="Buzz", Job="Developer"}, new { Name="Foo", Job="Astronaut"}, new { Name="Bar", Job="Astronaut"}, }; var groupedByJob = person...

class Developer { public int Id { get; set; } public string Name { get; set; } } class Project { public int DeveloperId { get; set; } public string Name { get; set; } } var developers = new[] { new Developer { Id = 1, Name = "Foobuzz" ...

Returns the Type of an object, without the need to instantiate it. Type type = typeof(string); Console.WriteLine(type.FullName); //System.String Console.WriteLine("Hello".GetType() == type); //True Console.WriteLine("Hello".GetType() == typeof(string)); //True

The namespace keyword is an organization construct that helps us understand how a codebase is arranged. Namespaces in C# are virtual spaces rather than being in a physical folder. namespace StackOverflow { namespace Documentation { namespace CSharp.Keywords { ...

public interface IAnimal { string Name { get; set; } } public interface INoiseMaker { string MakeNoise(); } public class Cat : IAnimal, INoiseMaker { public Cat() { Name = "Cat"; } public string Name { get; set; } public string M...

public class LivingBeing { string Name { get; set; } } public interface IAnimal { bool HasHair { get; set; } } public interface INoiseMaker { string MakeNoise(); } //Note that in C#, the base class name must come before the interface names public class Cat : LivingBei...

using System; using System.IO; using System.Net; using System.Net.Sockets; using System.Text; class TcpChat { static void Main(string[] args) { if(args.Length == 0) { Console.WriteLine("Basic TCP chat"); Console.WriteLine(); ...

The using static [Namespace.Type] directive allows the importing of static members of types and enumeration values. Extension methods are imported as extension methods (from just one type), not into top-level scope. 6.0 using static System.Console; using static System.ConsoleColor; using static ...

Overloading just equality operators is not enough. Under different circumstances, all of the following can be called: object.Equals and object.GetHashCode IEquatable<T>.Equals (optional, allows avoiding boxing) operator == and operator != (optional, allows using operators) When overrid...