' check the validity of the input data
If Not IsNumeric(UPCE) Then

You might want to consider using the following statement to reject
non-numeric values that are passed into you function instead of the above
statement...

' check the validity of the input data
If Value Like "*[!0-9]*" Then

To see why, consider this past posting of mine...

I usually try and steer people away from using IsNumeric to "proof"
supposedly numeric text. Consider this (also see note below):

ReturnValue = IsNumeric("($1,23,,3.4,,,5,,E67$)")

Most people would not expect THAT to return True. IsNumeric has some "flaws"
in what it considers a proper number and what most programmers are looking
for.

I had a short tip published by Pinnacle Publishing in their Visual Basic
Developer magazine that covered some of these flaws. Originally, the tip was
free to view but is now viewable only by subscribers.. Basically, it said
that IsNumeric returned True for things like -- currency symbols being
located in front or in back of the number as shown in my example (also
applies to plus, minus and blanks too); numbers surrounded by parentheses as
shown in my example (some people use these to mark negative numbers);
numbers containing any number of commas before a decimal point as shown in
my example; numbers in scientific notation (a number followed by an upper or
lower case "D" or "E", followed by a number equal to or less than 305 -- the
maximum power of 10 in VB); and Octal/Hexadecimal numbers (&H for
Hexadecimal, &O or just & in front of the number for Octal).

NOTE:
======
In the above example and in the referenced tip, I refer to $ signs and
commas and dots -- these were meant to refer to your currency, thousands
separator and decimal point symbols as defined in your local settings --
substitute your local regional symbols for these if appropriate.

As for your question about checking numbers, here are two functions that I
have posted in the past for similar questions..... one is for digits only
and the other is for "regular" numbers:

Function IsDigitsOnly(Value As String) As Boolean
IsDigitsOnly = Len(Value) 0 And _
Not Value Like "*[!0-9]*"
End Function

Function IsNumber(ByVal Value As String) As Boolean
' Leave the next statement out if you don't
' want to provide for plus/minus signs
If Value Like "[+-]*" Then Value = Mid$(Value, 2)
IsNumber = Not Value Like "*[!0-9.]*" And _
Not Value Like "*.*.*" And _
Len(Value) 0 And Value < "."
End Function

Here are revisions to the above functions that deal with the local settings
for decimal points (and thousand's separators) that are different than used
in the US (this code works in the US too, of course).

Function IsNumber(ByVal Value As String) As Boolean
Dim DP As String
' Get local setting for decimal point
DP = Format$(0, ".")
' Leave the next statement out if you don't
' want to provide for plus/minus signs
If Value Like "[+-]*" Then Value = Mid$(Value, 2)
IsNumber = Not Value Like "*[!0-9" & DP & "]*" And _
Not Value Like "*" & DP & "*" & DP & "*" And _
Len(Value) 0 And Value < DP
End Function

I'm not as concerned by the rejection of entries that include one or more
thousand's separators, but we can handle this if we don't insist on the
thousand's separator being located in the correct positions (in other words,
we'll allow the user to include them for their own purposes... we'll just
tolerate their presence).

Function IsNumber(ByVal Value As String) As Boolean
Dim DP As String
Dim TS As String
' Get local setting for decimal point
DP = Format$(0, ".")
' Get local setting for thousand's separator
' and eliminate them. Remove the next two lines
' if you don't want your users being able to
' type in the thousands separator at all.
TS = Mid$(Format$(1000, "#,###"), 2, 1)
Value = Replace$(Value, TS, "")
' Leave the next statement out if you don't
' want to provide for plus/minus signs
If Value Like "[+-]*" Then Value = Mid$(Value, 2)
IsNumber = Not Value Like "*[!0-9" & DP & "]*" And _
Not Value Like "*" & DP & "*" & DP & "*" And _
Len(Value) 0 And Value < DP
End Function

--
Rick (MVP - Excel)


"AFSSkier" wrote in message
...
I need some expert help with a VBA code. In excel I would like to have the
user input a TYPE-E UPC into B1 and after clicking a CmdBttn, have the
following code input the result of a Type-A UPC into B5 & the skip digit
into
B7.

Function UPCE2A(UPCE As String) As String

' check the validity of the input data
If Not IsNumeric(UPCE) Then
MsgBox ("UPC Codes must contain Numeric Data Only!")
Exit Sub
End If

Select Case Len(UPCE)
Case 6 ' do nothing everything is OK
UPCEString$ = UPCE
Case 7
UPCEString$ = Left$(UPCE, 6)
' truncate last digit - assume that it is the UPCE check digit
Case 8
UPCEString$ = Mid$(UPCE, 2, 6)
' truncate first and last digit
' assume that the first digit is the number system digit
' and the last digit is the UPCE check digit
Case Else
MsgBox "wrong size UPCE message"
Exit Sub
End Select

' break up the string into its 6 individual digits
Digit1$ = Mid$(UPCEString$, 1, 1)
Digit2$ = Mid$(UPCEString$, 2, 1)
Digit3$ = Mid$(UPCEString$, 3, 1)
Digit4$ = Mid$(UPCEString$, 4, 1)
Digit5$ = Mid$(UPCEString$, 5, 1)
Digit6$ = Mid$(UPCEString$, 6, 1)

Select Case Digit6$ ' expand the 6 digit UPCE number to a 12 digit
UPCA
number
Case "0", "1", "2"
ManufacturerNumber$ = Digit1$ + Digit2$ + Digit6$ + "00"
ItemNumber$ = "00" + Digit3$ + Digit4$ + Digit5$
Case "3"
ManufacturerNumber$ = Digit1$ + Digit2$ + Digit3$ + "00"
ItemNumber$ = "000" + Digit4$ + Digit5$ ' original code
was in error
Case "4"
ManufacturerNumber$ = Digit1$ + Digit2$ + Digit3$ + Digit4$ + "0"
ItemNumber$ = "0000" + Digit5$ ' original code was in
error
Case Else
ManufacturerNumber$ = Digit1$ + Digit2$ + Digit3$ + Digit4$ +
Digit5$
ItemNumber$ = "0000" + Digit6$
End Select

' put the number system digit "0" together with the manufacturer code and
Item number
Msg$ = "0" + ManufacturerNumber$ + ItemNumber$

' calculate the check digit - note UPCE and UPCA check digits are the same
Check% = 0 ' initialize the check digit value
For X% = 1 To 11
Test$ = Mid$(Msg$, X%, 1)
Select Case X%
Case 1, 3, 5, 7, 9, 11
Check% = Check% + Val(Test$) * 7 ' odd position digits
multiplied by 7
Case 2, 4, 6, 8, 10
Check% = Check% + Val(Test$) * 9 ' even position digits
multiplied by 9
End Select
Next

Check% = (Check% Mod 10) + 48 ' convert value to ASCII character value
CheckChar$ = Chr$(Check%) ' check character

UPCE2A = Msg$ + CheckChar$ ' put the pieces together and return
End Function

VBA Source: Differences between Type A and Type E UPCs at
http://www.taltech.com/TALtech_web/r...symbol.htm#UPC

--
Thanks, Kevin