C# 0 The Complete Reference

PART I

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PART IPART I

Although

ref

 and 

out

 participate in overload resolution, the difference between the two 

alone is not sufficient. For example, these two versions of 

MyMeth( )

 are invalid:

// Wrong!

public void MyMeth(out int x) { // ...

public void MyMeth(ref int x) { // ...

In this case, the compiler cannot differentiate between the two version of 

MyMeth( )

 simply 

because one uses an 

out int

 parameter and the other uses a 

ref int

 parameter.

Method overloading supports polymorphism because it is one way that C# 

implements the “one interface, multiple methods” paradigm. To understand how, 

consider the following. In languages that do not support method overloading, each 

method must be given a unique name. However, frequently you will want to implement 

essentially the same method for different types of data. Consider the absolute value 

function. In languages that do not support overloading, there are usually three or more 

versions of this function, each with a slightly different name. For instance, in C, the 

function