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# increment hexadecimal number in vbscript

This is VB script question, but we have no VB script area
so it is here. It is not webrelated.
Problem:
to increment hexadecimal number in vb script programmatically
(no data types)
for example you have
a = 00 00 00  now you want +1
and you want to go up to
a = ff ff ff ff
is it possible?

0
mativare
• 5
• 3
• 2
• +1
1 Solution

Commented:
Dim strA As String

strA = "0000"

Increment:

strA = Right("0000" & Hex(Clng("&H" & strA) + 1), 4)

Decrement:
strA = Right("0000" & Hex(Clng("&H" & strA) - 1), 4)

Et voilĂˇ
0

Commented:
Oh, that's integers. For longs:

strA = "00000000"

Increment:
If strA = "7FFFFFFF" Then
strA = "80000000"
Else
strA = Right("00000000" & Hex(Clng("&H" & strA) + 1), 8)
End If

Decrement:
If strA = "80000000" Then
strA = "7FFFFFFF"
Else
strA = Right("00000000" & Hex(Clng("&H" & strA) - 1), 8)
End If

The IF statements cater for the fact that longs are signed, and the range "00000000" to "FFFFFFFF" is not.
0

Billing EngineerCommented:
Public Function IncrementedHex(ByVal N)
Dim lngLoop
Dim blnOverflow
Dim Digit

blnOverflow = True
lngLoop = Len(N)
While blnOverflow
blnOverflow = False
If lngLoop = 0 Then
N = "1" & N
Else
Digit = Mid(N, lngLoop, 1)
If Digit = "F" Then
Mid(N, lngLoop, 1) = "0"
blnOverflow = True
Else
If IsNumeric(Digit) Then
If Digit = "9" Then
Mid(N, lngLoop, 1) = "A"
Else
Mid(N, lngLoop, 1) = Digit + 1
End If
Else
Mid(N, lngLoop, 1) = Chr(Asc(Digit) + 1)
End If
End If
End If
lngLoop = lngLoop - 1
Wend

IncrementedHex = N
End Function
0

Commented:
'Increments a 4 byte hex number represented as a string
Function IncHex(ByVal sHex As String)
Dim n1 As Long, n2 As Long
'n1 and n2 are the lo and hi order integers
n1 = CLng("&H" & Right(sHex, 4))
n2 = CLng("&H" & Left(sHex, 4))
n1 = n1 + 1
'Check for rollover 0000FFFF -> 00010000
If n1 > 65535 Then
n1 = 0
n2 = n2 + 1
'Check for rollover FFFFFFFF -> 00000000
If n2 > 65535 Then n2 = 0
End If
IncHex = String(4 - Len(Hex(n2)), "0") & Hex(n2) & _
String(4 - Len(Hex(n1)), "0") & Hex(n1)
End Function
0

Commented:
PS - you'll need to implement similar if statements for 7FFF and 8000 for Integers.
0

Commented:
..and use CInt instead of CLng

Sorry for the multiple posts.
0

Author Commented:
Adjusted points from 100 to 300
0

Author Commented:
So this is possible?
you are  good
some minor things
spaces are mission critical and
must be present at any time
the actual format is
00 00 00 00
it means Len must be 11
at any time
and position 3,6,9 must be empty
not even 0
I "incremented" points to 300

0

Commented:
'Increments a 4 byte hex number represented as a string
''Format of Hex - "00 00 00 00"
Function IncHex(ByVal sHex As String)
Dim n1 As Integer, n2 As Integer, n3 As Integer, n4 As Integer
'n1 - n4 are the lo to hi bytes
n1 = CInt("&H" & Mid(sHex, 10, 2))
n2 = CInt("&H" & Mid(sHex, 7, 2))
n3 = CInt("&H" & Mid(sHex, 4, 2))
n4 = CInt("&H" & Mid(sHex, 1, 2))

n1 = n1 + 1
If n1 > 255 Then
n1 = 0
n2 = n2 + 1
If n2 > 255 Then
n2 = 0
n3 = n3 + 1
If n3 > 255 Then
n3 = 0
n4 = n4 + 1
If n4 > 255 Then n4 = 0
End If
End If
End If
IncHex = Right("00" & Hex(n4), 2) & " " & _
Right("00" & Hex(n3), 2) & " " & _
Right("00" & Hex(n2), 2) & " " & _
Right("00" & Hex(n1), 2)
End Function
0

Commented:
strA = "00 00 00 00"

Increment:
If strA = "7F FF FF FF" Then
strA = "80 00 00 00"
Else
strA = Left(strA, 2) & Mid(strA, 4, 2) & Mid(strA, 7, 2) & Right(strA, 2)
strA = Right("00000000" & Hex(Clng("&H" & strA)  + 1), 8)
strA = Left(strA, 2) & " " & Mid(strA, 3, 2) & " " & Mid(strA, 5, 2) & " " & Right(strA, 2)

End If

I'm sure you can work out Decrement :-)
0

Author Commented:
Thank you
It functions and is short
0
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