When you write several constructors for a class, there are times when you would like to call one constructor from another to avoid duplicating code. You can do this using the this keyword.
Normally, when you say this, it is in the sense of ‘this object’ or the ‘current object’, and by itself it produces the handle to the current object. In a constructor, the this keyword takes on a different meaning when you give it an argument list: it makes an explicit call to the constructor that matches that argument list.