Exception Handling in VB.NET
This article will show how to use Exception Handling in VB.NET.
An exception is an error which occurred at run
time. there are four keyword which are used to find out error at the run time.
In Vb.NET is a special type of class called Exception which are used to pass the
message .
Try Statement:
Try statement is a block of statement that are
used to trap the error at run time. one try statement can have multiple catch
statement.
Syntax:
Try...[catch]...{catch|finally}......End Try
Catch Statement:
Catch statement catch the error from try
statement and execute the block of statement.
Syntax:
Catch [<exception>[As<type>]]
[when<expression>]
Finally Statement:
Finally statement are used to execute some
statement irrespective of error. Finally can only one block at the end.
Example: In this example one try
statement has more than one catch statement with the final statement and catch
statement catch different type of error from try statement.
Module
Module1
Sub
Main()
Dim
err As Boolean
= True
Dim
num As Integer
Try
Console.WriteLine("
please enter number:")
num =
Integer.Parse(Console.ReadLine())
Console.WriteLine("
you entered {0}", num)
err =
False
Catch
ex As
FormatException
Console.WriteLine("sorry:
kindly enter the number only ")
Catch
ex As
OverflowException
Console.WriteLine("
number is too large")
Catch
ex As
Exception
Console.WriteLine("critical
error occurred like copy, paste")
Finally
If
err = False Then
Console.WriteLine("
thanks for using system")
End
If
End
Try
End
Sub
End
Module
Output: Enter the
number
Output:
when we enter the character in place of number it calls the format exception.
Output: When we enter the large number
than the range of Integer it calls the overflowexception.
