System IO VB.Net by API

Imports System.IO
Module Module1
    Sub Main()
        Dim FileSt As FileStream = New FileStream("test.dat", FileMode.Create, FileAccess.Write, FileShare.Write)
        Try
            FileSt.Lock(0, 100)
            Console.WriteLine("Locked")
        Catch Ex As Exception
            Console.WriteLine(Ex.Message)
        End Try
        Try
            FileSt.Unlock(0, 100)
            Console.WriteLine("Unlocked")
        Catch Ex As Exception
            Console.WriteLine(Ex.Message)
        End Try
        Dim Values As Byte()
        Values = New Byte() {1, 2, 3, 4, 5}
        Try
            FileSt.Seek(0, SeekOrigin.Begin)
            FileSt.Write(Values, 0, 5)
            Console.WriteLine("Successfully updated file")
        Catch Ex As Exception
            Console.WriteLine(Ex.Message)
        End Try
    End Sub
End Module