Tutorial by Examples: en

// 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...

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 : " +...

using System; using System.IO; using System.Linq; using System.Net.Http; using System.Threading.Tasks; class HttpGet { private static async Task DownloadAsync(string fromUrl, string toFile) { using (var fileStream = File.OpenWrite(toFile)) { using (va...

using System.Text; //allows you to access classes within this namespace such as StringBuilder //without prefixing them with the namespace. i.e: //... var sb = new StringBuilder(); //instead of var sb = new System.Text.StringBuilder();

Notes: This example must be run in administrative mode. Only one simultaneous client is supported. For simplicity, filenames are assumed to be all ASCII (for the filename part in the Content-Disposition header) and file access errors are not handled. using System; using System.IO; using Syst...

var cancellationTokenSource = new CancellationTokenSource(); var cancellationToken = cancellationTokenSource.Token; var task = new Task((state) => { int i = 1; var myCancellationToken = (CancellationToken)state; while(true) { Console.Write...

var random = new Random(); IEnumerable<Task<int>> tasks = Enumerable.Range(1, 5).Select(n => Task.Run(async() => { Console.WriteLine("I'm task " + n); await Task.Delay(random.Next(10,1000)); return n; })); Task<Task<int>> whenAnyTask = Tas...

var random = new Random(); IEnumerable<Task<int>> tasks = Enumerable.Range(1, 5).Select(n => Task.Run(() => { Console.WriteLine("I'm task " + n); return n; })); Task<int[]> task = Task.WhenAll(tasks); int[] results = await task; Console.WriteLine...

The enum keyword tells the compiler that this class inherits from the abstract class Enum, without the programmer having to explicitly inherit it. Enum is a descendant of ValueType, which is intended for use with distinct set of named constants. public enum DaysOfWeek { Monday, Tuesday, ...

An enum is a special type of class. The enum keyword tells the compiler that this class inherits from the abstract System.Enum class. Enums are used for distinct lists of items. public enum MyEnum { Monday = 1, Tuesday, Wednesday, //... } You can think of an enum as a conve...

When passing formal arguments to a generic method, relevant generic type arguments can usually be inferred implicitly. If all generic type can be inferred, then specifying them in the syntax is optional. Consider the following generic method. It has one formal parameter and one generic type paramet...

A method can declare any number of parameters (in this example, i, s and o are the parameters): static void DoSomething(int i, string s, object o) { Console.WriteLine(String.Format("i={0}, s={1}, o={2}", i, s, o)); } Parameters can be used to pass values into a method, so that th...

public IEnumerable<User> SelectUsers() { // Execute an SQL query on a database. using (IDataReader reader = this.Database.ExecuteReader(CommandType.Text, "SELECT Id, Name FROM Users")) { while (reader.Read()) { int id = reader.GetInt32(0...

Just like other methods, extension methods can use generics. For example: static class Extensions { public static bool HasMoreThanThreeElements<T>(this IEnumerable<T> enumerable) { return enumerable.Take(4).Count() > 3; } } and calling it would be like: ...

Developers can be caught out by the fact that type inference doesn't work for constructors: class Tuple<T1,T2> { public Tuple(T1 value1, T2 value2) { } } var x = new Tuple(2, "two"); // This WON'T work... var y = new Tuple<int, string>(2, "t...

An iterator method is not executed until the return value is enumerated. It's therefore advantageous to assert preconditions outside of the iterator. public static IEnumerable<int> Count(int start, int count) { // The exception will throw when the method is called, not when the result i...

Unlike an expression lambda, a statement lambda can contain multiple statements separated by semicolons. delegate void ModifyInt(int input); ModifyInt addOneAndTellMe = x => { int result = x + 1; Console.WriteLine(result); }; Note that the statements are enclosed in braces {}. ...

See RFC 2030 for details on the SNTP protocol. using System; using System.Globalization; using System.Linq; using System.Net; using System.Net.Sockets; class SntpClient { const int SntpPort = 123; static DateTime BaseDate = new DateTime(1900, 1, 1); static void Main(string[...