var numbers = new[] {1,2,3,4};
var averageNumber = numbers.Average();
Console.WriteLine(averageNumber);
// 2,5
This method calculates the average of enumerable of numbers.
var cities = new[] {
new {Population = 1000},
new {Population = 2000},
new {Population = 4000}
};
v...
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();
...
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...
To make a class support collection initializers, it must implement IEnumerable interface and have at least one Add method. Since C# 6, any collection implementing IEnumerable can be extended with custom Add methods using extension methods.
class Program
{
static void Main()
{
va...
Backslash
// The filename will be c:\myfile.txt in both cases
string filename = "c:\\myfile.txt";
string filename = @"c:\myfile.txt";
The second example uses a verbatim string literal, which doesn't treat the backslash as an escape character.
Quotes
string text = "\&...
The ?. operator is syntactic sugar to avoid verbose null checks. It's also known as the Safe navigation operator.
Class used in the following example:
public class Person
{
public int Age { get; set; }
public string Name { get; set; }
public Person Spouse { get; set; }
}
If a...
// assign string from a string literal
string s = "hello";
// assign string from an array of characters
char[] chars = new char[] { 'h', 'e', 'l', 'l', 'o' };
string s = new string(chars, 0, chars.Length);
// assign string from a char pointer, derived from a string
string s;
uns...
// assigning a signed short to its minimum value
short s = -32768;
// assigning a signed short to its maximum value
short s = 32767;
// assigning a signed int to its minimum value
int i = -2147483648;
// assigning a signed int to its maximum value
int i = 2147483647;
// assigning a s...
// assigning an unsigned short to its minimum value
ushort s = 0;
// assigning an unsigned short to its maximum value
ushort s = 65535;
// assigning an unsigned int to its minimum value
uint i = 0;
// assigning an unsigned int to its maximum value
uint i = 4294967295;
// assigning an...
In order to be able to manage your projects' packages, you need the NuGet Package Manager. This is a Visual Studio Extension, explained in the official docs: Installing and Updating NuGet Client.
Starting with Visual Studio 2012, NuGet is included in every edition, and can be used from: Tools ->...
public class SomeClass
{
public void DoStuff()
{
}
protected void DoMagic()
{
}
}
public static class SomeClassExtensions
{
public static void DoStuffWrapper(this SomeClass someInstance)
{
someInstance.DoStuff(); // ok
...
You can enumerate through a Dictionary in one of 3 ways:
Using KeyValue pairs
Dictionary<int, string> dict = new Dictionary<int, string>();
foreach(KeyValuePair<int, string> kvp in dict)
{
Console.WriteLine("Key : " + kvp.Key.ToString() + ", Value : " +...
// Translates to `dict.Add(1, "First")` etc.
var dict = new Dictionary<int, string>()
{
{ 1, "First" },
{ 2, "Second" },
{ 3, "Third" }
};
// Translates to `dict[1] = "First"` etc.
// Works in C# 6.0.
var dict = new Dicti...
