C# 0 The Complete Reference

ob

. Then, the contents of 

ob

’s array are copied to the new 

array, and 

tos

 is set appropriately. After the constructor finishes, the new stack and the 

original stack are separate, but identical.

Invoke an Overloaded Constructor Through this

When working with overloaded constructors, it is sometimes useful for one constructor to 

invoke another. In C#, this is accomplished by using another form of the 

this

 keyword. The 

general form is shown here:

constructor-name

(

parameter-list1

) : this(

parameter-list2

) {

   // ... body of constructor, which may be empty

}

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When the constructor is executed, the overloaded constructor that matches the parameter 

list specified by 

parameter-list2

is first executed. Then, if there are any statements inside the 

original constructor, they are executed. Here is an example:

// Demonstrate invoking a constructor through this.

using System;

class XYCoord {

  public int x, y;

  public XYCoord() : this(0, 0) {

    Console.WriteLine("Inside XYCoord()");

  }

  public XYCoord(XYCoord obj) : this(obj.x, obj.y) {

    Console.WriteLine("Inside XYCoord(obj)");

  }

  public XYCoord(int i, int j) {

    Console.WriteLine("Inside XYCoord(int, int)");

    x = i;

    y = j;

  }

}

class OverloadConsDemo {

  static void Main() {

    XYCoord t1 = new XYCoord();

    XYCoord t2 = new XYCoord(8, 9);

    XYCoord t3 = new XYCoord(t2);

    Console.WriteLine("t1.x, t1.y: " + t1.x + ", " + t1.y);

    Console.WriteLine("t2.x, t2.y: " + t2.x + ", " + t2.y);

    Console.WriteLine("t3.x, t3.y: " + t3.x + ", " + t3.y);

  }

}

The output from the program is shown here:

Inside XYCoord(int, int)

Inside XYCoord()

Inside XYCoord(int, int)

Inside XYCoord(int, int)

Inside XYCoord(obj)

t1.x, t1.y: 0, 0

t2.x, t2.y: 8, 9

t3.x, t3.y: 8, 9

Here is how the program works. In the