May 16, 2002 - Defining Multiple Constructors | WebReference

May 16, 2002 - Defining Multiple Constructors

Yehuda Shiran May 16, 2002
Defining Multiple Constructors
Tips: May 2002

Yehuda Shiran, Ph.D.
Doc JavaScript

The following class is used to construct airplanes: 

  class Airplane {
    var model: int;
  
    function Airplane() {
      model = 767;
    }
  }
All airplanes instantiated using the Airplane class will be 767 because there's only one constructor that initializes the jet's model to 767. A class can have more than one constructor, as shown in the following listing:

  class Airplane {
    var model: int;
  
    function Airplane() {
      model = 767;
    }
  
    function Airplane(newModel : int) {
      model = newModel;
    }
  }
You can create a 767 using the class's default constructor:

  var thirdJet : Airplane;
  thirdJet = new Airplane();
You can also create a 777 by calling the second constructor (with the parameter):

  var fourthJet : Airplane;
  fourthJet = new Airplane(777);
To learn more about JScript .NET, go to Column 108, JScript .NET, Part II: Major Features.