Tutorial by Examples: r

Typically lambdas are used for defining simple functions (generally in the context of a linq expression): var incremented = myEnumerable.Select(x => x + 1); Here the return is implicit. However, it is also possible to pass actions as lambdas: myObservable.Do(x => Console.WriteLine(x)); ...

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...

Use parentheses around the expression to the left of the => operator to indicate multiple parameters. delegate int ModifyInt(int input1, int input2); ModifyInt multiplyTwoInts = (x,y) => x * y; Similarly, an empty set of parentheses indicates that the function does not accept parameters. ...

Imports System Module Program Public Sub Main() Console.WriteLine("Hello World") End Sub End Module Live Demo in Action at .NET Fiddle Introduction to Visual Basic .NET

Declaring an Event You can declare an event on any class or struct using the following syntax: public class MyClass { // Declares the event for MyClass public event EventHandler MyEvent; // Raises the MyEvent event public void RaiseEvent() { OnMyEvent(); }...

The left-hand operand must be nullable, while the right-hand operand may or may not be. The result will be typed accordingly. Non-nullable int? a = null; int b = 3; var output = a ?? b; var type = output.GetType(); Console.WriteLine($"Output Type :{type}"); Console.WriteLine($&q...

open System [<EntryPoint>] let main argv = printfn "Hello World" 0 Live Demo in Action at .NET Fiddle Introduction to F#

Explicit interface implementation is necessary when you implement multiple interfaces who define a common method, but different implementations are required depending on which interface is being used to call the method (note that you don't need explicit implementations if multiple interfaces share t...

// Connect to a target server using your ConnectionMultiplexer instance IServer server = conn.GetServer("localhost", 6379); // Write out each key in the server foreach(var key in server.Keys()) { Console.WriteLine(key); }

// Connect to a target server using your ConnectionMultiplexer instance IServer server = conn.GetServer("localhost", 6379); var seq = server.Keys(); IScanningCursor scanningCursor = (IScanningCursor)seq; // Use the cursor in some way...

public class SingletonClass { public static SingletonClass Instance { get; } = new SingletonClass(); private SingletonClass() { // Put custom constructor code here } } Because the constructor is private, no new instances of SingletonClass can be made by consum...

Returns a subset of items which the specified predicate is true for them. List<string> trees = new List<string>{ "Oak", "Birch", "Beech", "Elm", "Hazel", "Maple" }; Method syntax // Select all trees with name of length 3 v...

Select allows you to apply a transformation to every element in any data structure implementing IEnumerable. Getting the first character of each string in the following list: List<String> trees = new List<String>{ "Oak", "Birch", "Beech", "Elm", ...

using System.Speech.Recognition; // ... SpeechRecognitionEngine recognitionEngine = new SpeechRecognitionEngine(); recognitionEngine.LoadGrammar(new DictationGrammar()); recognitionEngine.SpeechRecognized += delegate(object sender, SpeechRecognizedEventArgs e) { Console.WriteLine(&quot...

SpeechRecognitionEngine recognitionEngine = new SpeechRecognitionEngine(); GrammarBuilder builder = new GrammarBuilder(); builder.Append(new Choices("I am", "You are", "He is", "She is", "We are", "They are")); builder.Append(new Choices...

Install the NuGet package System.Reactive, then add this using statement to access the Rx extension methods: using System.Reactive.Linq;

emails.Where(email => email.From == "John")

emails.Select(email => email.Body)

Subscription returns an IDisposable: IDisposable subscription = emails.Subscribe(email => Console.WriteLine("Email from {0} to {1}", email.From, email.To)); When you are ready to unsubscribe, simply dispose the subscription: subscription.Dispose();

emails.Subscribe(email => Console.WriteLine("Email from {0} to {1}", email.From, email.To), cancellationToken);