VB.Net/Language Basics/Catch Exception

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Catch All Unhandled Exceptions

<source lang="vbnet"> Imports System Imports System.Windows.Forms Imports System.IO Public Class MainClass

  Shared Sub Main()
       AddHandler Application.ThreadException, AddressOf app_ThreadException
       Application.OnThreadException(New InvalidDataException("There"))
       Throw New InvalidDataException("Here")
  End Sub 
  " Catch a ThreadException event.
   Shared Private Sub app_ThreadException(ByVal sender As Object, ByVal e As System.Threading.ThreadExceptionEventArgs)
       Console.WriteLine("Caught unhandled exception")
   End Sub

End Class

      </source>


Catch Exception Demo

<source lang="vbnet"> Imports System Public Class MainClass

 Shared Sub Main()
   Dim x As Int32 = 100
   Dim y As Int32 = 0
   Dim k As Int32
   Try
     k = x / y
   Catch e As Exception
     Console.WriteLine(e.Message)
   End Try
 End Sub
 

End Class


      </source>


Try and catch Exception: InvalidCastException

<source lang="vbnet"> Imports System Imports System.Diagnostics Public Class MainClass

   Shared Sub Main()
       Try
           Dim i As Integer = CInt("bad value")
       Catch ex As InvalidCastException
           Dim txt As String = "InvalidCastException"
           MsgBox(txt)
       Catch ex As Exception
           Dim txt As String = "Exception"
           MsgBox(txt)
       End Try
   End Sub

End Class


      </source>