C# 0 The Complete Reference

XYCoord

 class, the only constructor that actually 

initializes the 

x

 and 

y

 fields is 

XYCoord(int, int)

. The other two constructors simply invoke 

XYCoord(int, int)

 through 

this

. For example, when object 

t1

 is created, its constructor, 

XYCoord( )

, is called. This causes 

this(0, 0)

 to be executed, which in this case translates 

into a call to 

XYCoord(0, 0)

. The creation of 

t2

 works in similar fashion.

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PART I

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PART IPART I

One reason why invoking overloaded constructors through 

this

 can be useful is that 

it can prevent the unnecessary duplication of code. In the foregoing example, there is no 

reason for all three constructors to duplicate the same initialization sequence, which the use 

of

this

 avoids. Another advantage is that you can create constructors with implied “default 

arguments” that are used when these arguments are not explicitly specified. For example, 

you could create another 

XYCoord

 constructor as shown here:

public XYCoord(int x) : this(x, x) { }

This constructor automatically defaults the