Constructor

See also this recent thread where a similar question was asked:

http://www.c-sharpcorner.com/Forums/Thread/283962/why-constructor-has-not-return-type.aspx

That is because the constructors are used to create objects, they're void (thus they don't return anything), but the actual  purpose is just to create a new object, and set its value to null. 


After the constructor has been called, the object is set to null, and the object (in real) is stored on the heap, but the address of it is stored in the stack for accessing purposes. 

According to the C# 4.0 Language Specification, section 1.6:

Instances of classes are created using the new operator, which allocates memory for a new instance, invokes a constructor to initialize the instance, and returns a reference to the instance.

It is the new operator who is responsible of allocating memory, passing a reference of the newly allocated object to the constructor and then returning a reference to the instance. This mechanism is also explained in section 7.6.10.1:

The run-time processing of an object-creation-expression of the form new T(A), where T is class-type or a struct-type and A is an optional argument-list, consists of the following steps:

·         If T is a class-type:

o    A new instance of class T is allocated. If there is not enough memory available to allocate the new instance, a System.OutOfMemoryException is thrown and no further steps are executed.

o    All fields of the new instance are initialized to their default values (§5.2).

o    The instance constructor is invoked according to the rules of function member invocation (§7.5.4). A reference to the newly allocated instance is automatically passed to the instance constructor and the instance can be accessed from within that constructor as this.

·         […]

This would mean that the constructor per se has no return type (void).