Exception Handling Examples

Example : Exception Handling Examples in VB .Net to show the concept of System Exception Handling.

Module Module1
    Sub division(ByVal num1 As Integer, ByVal num2 As Integer)
        Dim result As Integer

        Try
            result = num1 \ num2
        Catch ex As DivideByZeroException
            Console.WriteLine("The arised Exception is = : {0}", ex)
        Finally
            Console.WriteLine("The output is =: {0}", result)
        End Try

    End Sub

    Sub Main()
        division(40, 0)
       'division(40, 5)
        Console.ReadKey()
    End Sub

End Module

-----------  OR  -----------

Module Module1
    Sub division(ByVal num1 As Integer, ByVal num2 As Integer)
        Dim result As Integer

        Try
            result = num1 \ num2
        Catch ex As Exception

            Console.WriteLine("The arised Exception is = : {0}", ex)
        Finally
            Console.WriteLine("The output is =: {0}", result)
        End Try

    End Sub

    Sub Main()
        division(40, 0)
        'division(40, 5)
        Console.ReadKey()
    End Sub

End Module

Output:
The arised Exception is = : System.DivideByZeroException: Attempted to divide by zero.
   at ConsoleApplication2.Module1.division(Int32 num1, Int32 num2) in C:\Users\RAJ\Desktop\ConsoleApplication2\ConsoleApplication2\Module1.vb:line 5
The output is =: 0

Example : Exception Handling Examples in VB .Net to show the User Defined Exception Handling concept.

Imports System
Module Module1
    Sub Main()
        Dim str1 As String = "Welcome"
        Try
            If str1.Length > 0 Then 'Not throws an exception when condition is True
                Console.WriteLine(" The String is {0}", str1)
            End If
        Catch ex As Exception  ' it will cacthe an exception  
            Console.WriteLine("The exception message is {0}", ex.Message)
        End Try

        Console.WriteLine(" Press any key to exit...")
        Console.ReadKey()
    End Sub
End Module

Output:
 The String is Welcome
 Press any key to exit...

------------------  OR  ------------------

Imports System
Module Module1
    Sub Main()
        Dim str1 As String = Nothing
        Try
            If str1.Length > 0 Then  'throws an exception when condition is False
                Console.WriteLine(" The String is {0}", str1)
            End If
        Catch ex As Exception  ' it will cacthe an exception  
            Console.WriteLine("The exception message is {0}", ex.Message)
        End Try

        Console.WriteLine(" Press any key to exit...")
        Console.ReadKey()
    End Sub
End Module

Output:
The exception message is Object reference not set to an instance of an object.
 Press any key to exit...

------------------  OR  ------------------

Module Module1
    Sub Main()
        Try
            Throw New ApplicationException("Message for a User defined exception")
        Catch ex As Exception
            Console.WriteLine("The user defined exception is : " & ex.Message)
        Finally
            Console.WriteLine("The Finally Block is executed")
        End Try
        Console.ReadKey()
    End Sub
End Module

Output:
The user defined exception is : Message for a User defined exception
The Finally Block is executed

Example : Exception Handling Examples in VB .Net to show the concept of Multiple Catch Statements.

Imports System
Module Module1
    Sub Main()
        Dim value1 As Integer = 0
        Dim value2 As Integer = 0
        Dim result As Integer = 0

        Try
            Console.Write("Enter First Value: ")
            value1 = Integer.Parse(Console.ReadLine())

            Console.Write("Enter Second Value: ")
            value2 = Integer.Parse(Console.ReadLine())

            result = value1 \ value2
            Console.WriteLine("result : " + result)

        Catch e As DivideByZeroException
            Console.WriteLine(e.Message)
        Catch e As FormatException
            Console.WriteLine("Format exception")
        Catch e As Exception
            Console.WriteLine("Other exception")
        End Try

    End Sub
End Module

Output:
   
   Enter First Value: 10
   Enter Second Value: 0
   Attempted to divide by zero.
   
   Enter First Value: 12
   Enter Second Value: 3.2
   Format exception

   Enter First Value: 10
   Enter Second Value: 2
   Other exception