Why is binaryreader stripping first byte of my file?

Question

So I am writing a program that will receive settings from a binary file in vb.net. I am reading 25 bytes at a time. However when I retrieve my byte array it is missing the first byte, and only the first byte.

        Dim bytes(24) As Byte
        Using fs As BinaryReader = New BinaryReader(File.Open(folder.SelectedPath & "\*********", FileMode.Open, FileAccess.Read))
            While fs.Read() > 0
                fs.Read(bytes, 0, bytes.Length)
            End While
            fs.Close()
        End Using

My resulting array will miss only the first byte which in my case is 0x40. Why is this happening and what should I do to avoid this?

Answer 1

It is because the fs.Read in While fs.Read() > 0 reads something from the stream, and thus the stream is no longer at position 0.

Here is how you should do it:

Dim bytes(24) As Byte
Using fs As BinaryReader = New BinaryReader(File.Open(folder.SelectedPath & "\*********", FileMode.Open, FileAccess.Read))

    Dim total_read As Integer

    While total_read < bytes.Length
        Dim read = fs.Read(bytes, total_read, bytes.Length - total_read)
        If read = 0 Then
            Exit While
        End If

        total_read += read
    End While
End Using