visual basic 2008 voorbeelden en boeken / visual basic 2010 voorbeelden en boeken

Module IOExceptionsExample
    Sub Main()
        Dim path As String = "..."
        Dim streamReader As System.IO.StreamReader
        Try
            streamReader = New System.IO.StreamReader(path)
            Try
                streamReader.ReadToEnd() ' or : streamReader.ReadLine()
            Catch ex As System.OutOfMemoryException
                ' there is insufficient memory to allocate a buffer for
                ' the returned string
            Catch ex As System.IO.IOException
                ' an I/O error occurs
            End Try
        Catch ex As System.ArgumentNullException
            ' path is null
        Catch ex As System.ArgumentException
            ' path is an empty string
        Catch ex As System.IO.FileNotFoundException
            ' the file cannot be found
        Catch ex As System.IO.DirectoryNotFoundException
            ' the specified path is invalid, such as being on an unmapped drive
        Catch ex As System.IO.IOException
            ' path includes an incorrect or invalid syntax for file name,
            ' directory name, or volume label
        Finally
            If streamReader IsNot Nothing Then streamReader.Close()
        End Try
        '
        Dim streamWriter As System.IO.StreamWriter
        Try
            streamWriter = New System.IO.StreamWriter(path)
            Try
                streamWriter.Write("...")
            Catch ex As System.ObjectDisposedException
                ' AutoFlush is true or the buffer is full, and current writer
                ' is closed.
            Catch ex As System.NotSupportedException
                ' AutoFlush is true or buffer is full, and the contents of the
                ' buffer cannot be written to the underlying fixed size stream
                ' because the cursor is at the end the stream
            Catch ex As System.IO.IOException
                ' an I/O error occurs
            End Try
        Catch ex As System.UnauthorizedAccessException
            ' access is denied
        Catch ex As System.ArgumentNullException
            ' path is null
        Catch ex As System.ArgumentException
            ' path is an empty string ( "" ) or path contains the name of a
            ' system device (com1, com2, and so on)
        Catch ex As System.IO.DirectoryNotFoundException
            ' the specified path is invalid, such as being on an unmapped drive
        Catch ex As System.IO.PathTooLongException
            ' the specified path, file name, or both exceed the system-defined
            ' maximum length
        Catch ex As System.IO.IOException
            ' path includes an incorrect or invalid syntax for file name,
            ' directory name, or volume label syntax
        Catch ex As System.Security.SecurityException
            ' the caller does not have the required permission
        Finally
            If streamWriter IsNot Nothing Then streamWriter.Close()
        End Try
        '
        Console.ReadLine()
    End Sub
End Module