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Constructors in C#

C# supports both instance and static constructors. An instance constructor is a member that implements the actions required to initialize an instance of a class. A static constructor is a member that implements the actions required to initialize a class itself when it is first loaded.

A constructor is declared like a method with no return type and the same name as the containing class. If a constructor declaration includes a static modifier, it declares a static constructor. Otherwise, it declares an instance constructor.


Instance constructors can be overloaded. For example, the List<T> class declares two instance constructors, one with no parameters and one that takes an int parameter. Instance constructors are invoked using the new operator. The following statements allocate two List<string> instances using each of the constructors of the List class.

List<string> list1 = new List<string>();
List<string> list2 = new List<string>(10);
Unlike other members, instance constructors are not inherited, and a class has no instance constructors other than those actually declared in the class. If no instance constructor is supplied for a class, then an empty one with no parameters is automatically provided.
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