Tutorial by Examples: en

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(); }...

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...

It is possible to use multiple nested using statements without added multiple levels of nested braces. For example: using (var input = File.OpenRead("input.txt")) { using (var output = File.OpenWrite("output.txt")) { input.CopyTo(output); } // output is ...

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", ...

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

string helloWorld = "Hello World!"; string world = helloWorld.Substring(6); //world = "World!" string hello = helloWorld.Substring(0,5); // hello = "Hello" Substring returns the string up from a given index, or between two indexes (both inclusive).

string HelloWorld = "Hello World"; HelloWorld.StartsWith("Hello"); // true HelloWorld.StartsWith("Foo"); // false Finding a string within a string Using the System.String.Contains you can find out if a particular string exists within a string. The method returns ...

String.Trim() string x = " Hello World! "; string y = x.Trim(); // "Hello World!" string q = "{(Hi!*"; string r = q.Trim( '(', '*', '{' ); // "Hi!" String.TrimStart() and String.TrimEnd() string q = "{(Hi*"; string r = q.TrimStart( '{...

Unlike interfaces, which can be described as contracts for implementation, abstract classes act as contracts for extension. An abstract class cannot be instantiated, it must be extended and the resulting class (or derived class) can then be instantiated. Abstract classes are used to provide generi...

Event declaration: public event EventHandler<EventArgsT> EventName; Event handler declaration: public void HandlerName(object sender, EventArgsT args) { /* Handler logic */ } Subscribing to the event: Dynamically: EventName += HandlerName; Through the Designer: Click the Events...

Event declaration: public event EventHandler<EventArgsType> EventName; Event handler declaration using lambda operator => and subscribing to the event: EventName += (obj, eventArgs) => { /* Handler logic */ }; Event handler declaration using delegate anonymous method syntax: Eve...

Events can be of any delegate type, not just EventHandler and EventHandler<T>. For example: //Declaring an event public event Action<Param1Type, Param2Type, ...> EventName; This is used similarly to standard EventHandler events: //Adding a named event handler public void HandlerNa...

var sequenceOfSequences = new [] { new [] { 1, 2, 3 }, new [] { 4, 5 }, new [] { 6 } }; var sequence = sequenceOfSequences.SelectMany(x => x); // returns { 1, 2, 3, 4, 5, 6 } Use SelectMany() if you have, or you are creating a sequence of sequences, but you want the result as one long sequen...

The following examples will not compile: string s = "\c"; char c = '\c'; Instead, they will produce the error Unrecognized escape sequence at compile time.

The nameof operator allows you to get the name of a variable, type or member in string form without hard-coding it as a literal. The operation is evaluated at compile-time, which means that you can rename, using an IDE's rename feature, a referenced identifier and the name string will update with it...

Snippet public class Person : INotifyPropertyChanged { private string _address; public event PropertyChangedEventHandler PropertyChanged; private void OnPropertyChanged(string propertyName) { PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName))...

Snippet public class BugReport : INotifyPropertyChanged { public string Title { ... } public BugStatus Status { ... } } ... private void BugReport_PropertyChanged(object sender, PropertyChangedEventArgs e) { var bugReport = (BugReport)sender; switch (e.PropertyName) ...

Snippet public class SomeClass<TItem> { public void PrintTypeName() { Console.WriteLine(nameof(TItem)); } } ... var myClass = new SomeClass<int>(); myClass.PrintTypeName(); Console.WriteLine(nameof(SomeClass<int>)); Console Output TItem S...

Snippet Console.WriteLine(nameof(CompanyNamespace.MyNamespace)); Console.WriteLine(nameof(MyClass)); Console.WriteLine(nameof(MyClass.MyNestedClass)); Console.WriteLine(nameof(MyNamespace.MyClass.MyNestedClass.MyStaticProperty)); Console Output MyNamespace MyClass MyNestedClass MyStatic...

Create a property with getter and/or setter and initialize all in one line: public string Foobar { get; set; } = "xyz";