This document discusses exception handling in C#. It defines an exception as a problem that arises during program execution, such as dividing by zero. It describes how try, catch, and finally keywords allow programmers to transfer control when exceptions occur. The try block identifies code that could cause exceptions. Catch blocks handle specific exception types. Finally blocks contain code that always executes regardless of exceptions. Common exception classes derive from System.Exception. The example shows a method catching and handling a DivideByZeroException using try, catch, and finally.

1. Exception Handling in C#
Anul Chaudhary
131CC00304

2. Contents
Example
Exception Classes in c#
Syntax
Exception handling
What is an exception error?
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3. What is an exception ?
 An exception is a problem that arises
during the execution of a program.
 A C# exception is a response to an
exceptional situation that arises while a
program is running, such as an attempt to
divide by zero.
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4.  Exceptions provide a way to transfer
control from one part of a program to
another.
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5. Exception handling
 C# exception handling is built upon four keywords:
 try: A try block identifies a block of code for
which particular exceptions will be activated.
It's followed by one or more catch blocks.
 catch: A program catches an exception with an
exception handler at the place in a program
where you want to handle the problem. The
catch keyword indicates the catching of an
exception.
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6.  finally: The finally block is used to execute a given
set of statements, whether an exception is thrown or
not thrown.
For example, if you open a file, it must be closed
whether an exception is raised or not.
 throw: A program throws an exception when a
problem shows up. This is done using a throw
keyword.
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7. Syntax
 Assuming a block will raise and exception, a
method catches an exception using a combination
of the try and catch keywords.
 You can list down multiple catch statements to
catch different type of exceptions in case your try
block raises more than one exception in different
situations.
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9. working of try & catch
Try
block
Catch
block
Statement
that
Cause
Exception
Statement
that
Cause
Exception

10. working of try & catch with
Finally
Try Block
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Finally
Catch BlockFinally

11. Exception Classes in C#
 Exceptions in .NET are objects
 The System.Exception class is base
for all exceptions in CLR
 Contains information for the cause of
the error / unusual situation
Message – text description of the
exception
StackTrace – the snapshot of the stack
at the moment of exception throwing
InnerException – exception caused
the current
exception (if any)

13.  The System.ApplicationException class
supports exceptions generated by
application programs.
 So the exceptions defined by the
programmers should derive from this class.
 The System.SystemException class is the
base class for all predefined system
exception.
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14. Exception Classes in C#
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15. Example 1
1. class Program {
2. public static void division(int num1, int num2)
3. {
4. float result=0.0f;
5. try
6. {
7. result = num1 / num2;
8. }
9. catch (DivideByZeroException e)
10. {
11. Console.WriteLine("Exception Error !! n divide by zero !!");
12. // Console.WriteLine("Exception caught: {0}", e);
13. }

16. 1. finally
2. {
3. Console.WriteLine("Result: {0} ", result);
4. }
5. }
6. static void Main(string[] args)
7. {
8. division(10,0);
9. Console.ReadLine();
10. } }

17. Conclusion
The conclusion is that by using try, Catch and finally block
we can avoid exception occurring in the program and can
also display its type.

18. Thank You