C# 0 The Complete Reference

PART I

C h a p t e r   1 3 :  

E x c e p t i o n   H a n d l i n g  

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PART IPART I

Most of the exceptions in Table 13-1 are self-explanatory, with the possible exception of 

NullReferenceException

. This exception is thrown when there is an attempt to use a null 

reference as if it referred to an object—for example, if you attempt to call a method on a null 

reference. A 

null reference

 is a reference that does not point to any object. One way to create a 

null reference is to explicitly assign it the value null by using the keyword 

null

. Null references 

can also occur in other ways that are less obvious. Here is a program that demonstrates the