Tutorial by Examples: d

// 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...

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...

Dictionary<int, string> dict = new Dictionary<int, string>(); dict.Add(1, "First"); dict.Add(2, "Second"); // To safely add items (check to ensure item does not already exist - would throw) if(!dict.ContainsKey(3)) { dict.Add(3, "Third"); } Al...

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...

The checked and unchecked keywords define how operations handle mathematical overflow. "Overflow" in the context of the checked and unchecked keywords is when an integer arithmetic operation results in a value which is greater in magnitude than the target data type can represent. When ove...

List<int> l2 = l1.FindAll(x => x > 6); Here x => x > 6 is a lambda expression acting as a predicate that makes sure that only elements above 6 are returned.

When you want to catch an exception and do something, but you can't continue execution of the current block of code because of the exception, you may want to rethrow the exception to the next exception handler in the call stack. There are good ways and bad ways to do this. private static void AskTh...

public class Model { public string Name { get; set; } public bool? Selected { get; set; } } Here we have a Class with no constructor with two properties: Name and a nullable boolean property Selected. If we wanted to initialize a List<Model>, there are a few different ways to ex...

public delegate int ModifyInt(int input); ModifyInt multiplyByTwo = x => x * 2; The above Lambda expression syntax is equivalent to the following verbose code: public delegate int ModifyInt(int input); ModifyInt multiplyByTwo = delegate(int x){ return x * 2; };

class Program { static void Main(string[] args) { // Create 2 thread objects. We're using delegates because we need to pass // parameters to the threads. var thread1 = new Thread(new ThreadStart(() => PerformAction(1))); var thread2 = new Thread(...

var zipcode = myEmployee?.Address?.ZipCode; //returns null if the left operand is null. //the above is the equivalent of: var zipcode = (string)null; if (myEmployee != null && myEmployee.Address != null) zipcode = myEmployee.Address.ZipCode;

var letters = "letters".ToCharArray(); char letter = letters[1]; Console.WriteLine("Second Letter is {0}",letter); //in the above example we take the second character from the array //by calling letters[1] //NB: Array Indexing starts at 0; i.e. the first letter would be give...

var letters = null; char? letter = letters?[1]; Console.WriteLine("Second Letter is {0}",letter); //in the above example rather than throwing an error because letters is null //letter is assigned the value null

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...

The ConfigurationManager class supports the AppSettings property, which allows you to continue reading settings from the appSettings section of a configuration file the same way as .NET 1.x supported. app.config <?xml version="1.0" encoding="utf-8"?> <configuration&gt...

Visual Studio helps manage user and application settings. Using this approach has these benefits over using the appSettings section of the configuration file. Settings can be made strongly typed. Any type which can be serialized can be used for a settings value. Application settings can be...

Starting from a new Settings class and custom configuration section: Add an application setting named ExampleTimeout, using the time System.Timespan, and set the value to 1 minute: Save the Project Properties, which saves the Settings tab entries, as well as re-generates the custom Settings cl...

var collection = new BlockingCollection<int>(5); var random = new Random(); var producerTask = Task.Run(() => { for(int item=1; item<=10; item++) { collection.Add(item); Console.WriteLine("Produced: " + item); Thread.Sleep(random.Next(1...