Use of using statement in c#

• using is used when you have a resource that you want disposed after it's been used.
• The using statement obtains the resource specified, executes the statements and
  finally calls the Dispose method of the object to clean up the object.
• This is basically used to release the  Resources that are no longer in use.
• When the code block exits the scope of the using statement, Dispose() is called implicitly.

using (SqlConnection con = new SqlConnection(AppConfiguration.ConnectionString))
            {

            }

The above block implicitily convert as follwoing

try
{
SqlConnection con = new SqlConnection(AppConfiguration.ConnectionString)
}
finally
{
if(con!=null)
{
 ((IDisposable)con).Dispose();
}
}