в 16:40, 26 мая 2010

2010-05-26T16:40:30Z

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2010-05-26T12:53:42Z

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==Close Stream in Finally statement==

<source lang="vbnet">Imports System.IO
public class Test
public Shared Sub Main
Dim srReader As IO.StreamReader
Dim strLine As String
Dim blnDone As Boolean = False
Dim strFileName As String = "test.txt"
"Read text from a file and display it in a list box.
srReader = New IO.StreamReader(strFileName)
Try
While Not blnDone
strLine = srReader.ReadLine()
If strLine Is Nothing Then
blnDone = True
Else
Console.WriteLine(strLine)
End If
End While
srReader.Close()
Catch ex As Exception
Console.WriteLine("An error has occurred.")
Finally
srReader.Close()
End Try

End Sub
End class</source>

==Finally after multiple catch statements==

<source lang="vbnet">Module Module1
Sub Main()
Dim intItem1 As Integer = 0
Dim intItem2 As Integer = 128
Dim intResult As Integer
Try
intResult = intItem2 / intItem1
Catch e As OverflowException
Console.WriteLine("An overflow exception occurred.")
Catch e As OutOfMemoryException
Console.WriteLine("Out of memory.")
Catch e As IndexOutOfRangeException
Console.WriteLine("Array index out of range.")
Finally
Console.WriteLine("Finally")
End Try
End Sub
End Module</source>
<pre class=codeResult>An overflow exception occurred.
Finally</pre>

==Finally always executes==

<source lang="vbnet">Public Class Tester
Public Shared Sub Main
DoesNotThrowException()
End Sub
Public Shared Sub DoesNotThrowException()
Try
Console.WriteLine("In DoesNotThrowException")
Catch
Console.WriteLine("This Catch never executes")
Finally
Console.WriteLine("Finally executed in DoesNotThrowException")
End Try
Console.WriteLine("End of DoesNotThrowException")
End Sub " DoesNotThrowException
End Class</source>
<pre class=codeResult>In DoesNotThrowException
Finally executed in DoesNotThrowException
End of DoesNotThrowException</pre>

==Try Catch with Finally clause==

<source lang="vbnet">Option Strict On
Imports System
Class Tester
Public Shared Function DoDivide(ByVal a As Double, ByVal b As Double) As Double
If b = 0 Then
Throw New System.DivideByZeroException( )
End If
If a = 0 Then
Throw New System.ArithmeticException( )
End If
Return a / b
End Function "DoDivide
Shared Sub Main( )
Try
Console.WriteLine("Open file here")
Dim a As Double = 5
Dim b As Double = 0
Console.WriteLine("{0} / {1} = {2}", a, b, DoDivide(a, b))
Console.WriteLine("This line may or may not print")
Catch e As System.DivideByZeroException
Console.WriteLine("DivideByZeroException caught!")
Catch
Console.WriteLine("Unknown exception caught!")
Finally
Console.WriteLine("Close file here.")
End Try
End Sub
End Class</source>
<pre class=codeResult>Open file here
DivideByZeroException caught!
Close file here.</pre>

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в 16:40, 26 мая 2010

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