There are a number of exception classes provided by C#, all of which inherit from the System.Exception class. Following are some common exception classes.

The finally block is used to do all the clean up code. It does not support the error message, but all the code contained in the finally block is executed after the exception is raised. We can use this block along with try-catch and only with catch too.

The finally block is executed even if the error is raised. Control is always passed to the finally block regardless of how the try blocks exits.

This is shown in the following example:

int a, b = 0 ;
Console.WriteLine( "My program starts" ) ;
try
{
 a = 10 / b;
}
catch ( InvalidOperationException e )
{
 Console.WriteLine ( e ) ;
}
catch ( DivideByZeroException e)
{
 Console.WriteLine ( e ) ;
}
finally
{
 Console.WriteLine ( "finally" ) ; 
}
Console.WriteLine ( "Remaining program" ) ; 

My program starts
System.DivideByZeroException: Attempted to divide by zero.
at ConsoleApplication4.Class1.Main(String[] args) in d:\programs\consoleapplication4\class1.cs:line 51
finally
Remaining program

But then what's the difference? We could have written

Console.WriteLine ("finally");

after the catch block, and not write the finally block at all. Writing finally did not make much of a difference. Anyway the code written after catch gets executed. The answer to this is not clear in this program. It will be clear when we see the try-finally and the throw statement.