Multiple Catch Blocks for Try Block in C#

              In this article, I would like to know you about multiple catch blocks for try block.

Actually the Exception class is the super class for all the exceptions, so this Exception class catch block should be at end of all catch blocks, if not it shows an error message at compile time only i.e., A previous catch clause already catches all exceptions of this or of a super type ('Exception').

So that to avoid compile time errors, we have to set the order of different exception catch blocks.

The below example is the sample program that shows the  order of the catch block exceptions :

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace CSHARP_MultipleCatchBlocks

{

    class Program

    {

        static void Main(string[] args)

        {

            try

            {

                Console.Write("Enter a value : ");

                int? numerator = int.Parse(Console.ReadLine());

                Console.Write("Enter b value : ");

                int? denominator = int.Parse(Console.ReadLine());

                int? result = numerator / denominator;

                Console.WriteLine("Division Of numerator/denominator : {0}", result);

                Console.ReadKey();

            }

            //// If catch block with parameter class Exception is written first, then the following error message come at compile time

            //// A previous catch clause already catches all exceptions of this or of a super type ('Exception')

            //// If given value is more than the datatype size then ArithmeticException Occurs

            catch (DivideByZeroException ex)  // Here DivideByZeroException is written first because it is derived from ArithmeticException, if not it shows the compile time error as same as above

            {

                Console.WriteLine(ex.Message.ToString() + " DivideByZero Exception");

                Console.ReadKey();

            }

            //// If given value is more than the datatype size then ArithmeticException Occurs

            catch (ArithmeticException ex)

            {

                Console.WriteLine(ex.Message.ToString() + " Arithmetic Exception");

                Console.ReadKey();

            }

          

            //// If given value datatype is not supports by existing declared datatype then FormatException Occurs

            catch (FormatException ex)

            {

                Console.Write(ex.Message.ToString() + " Format Exception");

                Console.ReadKey();

            }

            // This catch block should be last, because this is the super class for all exceptions

            catch (Exception ex)

            {

                Console.WriteLine(ex.Message.ToString() + " Base Exception");

                Console.ReadKey();

            }

        }

    }

}

Output:

When we run the application it displays as :

Enter only the integer values in numerator and denominator variables. It display as below :

Now enter the denominator value zero, then it executes the  DivideByZeroException catch block and throws exception as shown below :

Now enter the numerator or denominator value more than the size of the  int datatype, then it executes the ArithmeticException catch block and throws exception as shown below :

Now enter the numerator or denominator value other than  the  int  datatype, like string, float etc, then it executes the FormatException catch block and throws exception as shown below :

Download Code From GitHub