reading bytes in reverse order

I need to read three bytes at the following offsets: 13583, 13584, 13585. Except, I need to read them in reverse order (13585, 13584, 13583)

Say the bytes in those offsets are so:

13583 = 0E
13584 = 45
13585 = 1F

Now in normal reading order it would be 0E451F which would be 935199 in decimal. But, in reverse order (the order i need) it would be 1F450E or 2049294 decimal.

I have no clue how I can do this. I spent about 45 minutes looking through the object editor and found nothing that would help me. Any ideas

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reading bytes in reverse order

plmokn

        Dim hi, mid, lo As Byte
        Dim i As Integer = &HAABBCC
        hi = (i And &HFF)
        mid = (i >> 8) And &HFF
        lo = (i >> 16) And &HFF

        ' Start int: AABBCC, hi: AA, mid: BB, lo: CC
wuchisan
That "computation" didn't work. I had the following values

13583 = 00
13584 = 00
13585 = 01

So, in reverse order it would be 10000h or 65536 decimal. But, the code you provided resulted in a 1 being displayed. It's almost like it completely ignored the zeros. I also tried it with all three bytes equaling 11h and it resulted in 17 (111111h is 1118481 in decimal)

this is the code I got:

Protected charExp As UInt32
charExp = (b(13585) << 16) Or (b(13584) << 8) Or b(13583)

Any ideas
Arild Fines
Dim foo as integer

foo = ((foo Or B(13585 )) << 16) Or ((foo Or B(13584)) << 8) Or B(13583)

It's simply called ....computing....
Rob Volk

Dim foo as integer = (B(13585 ) << 16) or (B(13584) << 8) or B(13583)

It's simply called ....computing....
rad_siri
Ok, I use the following code to read the bytes:

charExp = ((CUInt(b(13585))) << 16) Or ((CUInt(b(13584))) << 8) Or b(13583)

now what would I use to set the value back to the buffer I have been looking through that link you gave for the past 3 days Johan, but I cannot find what I am looking for. I got the following sub for setting a 16bit value back to the buffer:

Private Sub ConvertToBytes(ByVal int As Integer, ByVal b As Byte(), ByVal Offset As Integer)
Dim t As Integer = int
b(Offset) = t And &HFF
t = t >> 8
If t = 0 Then Exit Sub
b(Offset + 1) = t And &HFF
End Sub

That works, but only for 16bit values and only in normal order. The value I am working with is indeed a strange value, using only 3 bytes. Plus, it is in reverse order. I understand bitwise operators a little bit, it's just the reverse order thing that is giving me trouble. Any ideas on how I would write this back to the buffer
kosinsky

Or, as an alternate solution:

charExp = (CUInt(b(13585)) << 16) Or (CUInt(b(13584)) << 8) Or b(13583)

For more info on exactly how the shift operators work in Visual Basic.NET, check out:

http://msdn.microsoft.com/library/default.asp url=/library/en-us/vbls7/html/vblrfvbspec11_11.asp

Best regards,
Johan Stenberg
DennisV
It's simply called ....Thanks, worked perfectly....
reading bytes in reverse order

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