Identifying Digit-Only Part Numbers Excluding Special Characters

Re. my most recent comment below, VBA's Like operator supports limited patterns but a regular expression has more features. Therefore, all these cell formulas match the Tip's DigitsOnly(A1) result
    =NOT(IsRegEx(A1,"[^\d\s/-]+"))
    =NOT(IsRegEx(A1,"[^0-9 /-]+"))
    =NOT(IsRegEx(A1,"[^0123456789 /-]+"))
    =NOT(IsLike(A1,"*[!0123456789 /-]*"))
    =NOT(IsLike(A1,"*[!0-9 /-]*"))
See https://www.tutorialspoint.com/vbscript/vbscript_reg_expressions.htm
and https://learn.microsoft.com/en-us/office/vba/language/reference/user-interface-help/like-operator

My Excel Toolbox now includes the following IsRegEx function for convenient use of VBScript.RegExp to compare Text with a regular expression Pattern:

Public Function IsRegEx(Text As String, Pattern As String) As Boolean
    With CreateObject("VBScript.RegExp")
        .Pattern = Pattern
        IsRegEx = .Test(Text)
    End With
End Function

Reviewing my previous comment below, these cell formulas match the Tip's DigitsOnly(A1) result
    =NOT(IsRegEx(A1,"[^0123456789 /-]+"))
    =NOT(IsLike(A1,"*[!0123456789 /-]*"))
and these cell formulas help Chris identify cells with part numbers having one or more digits but no letters
    =AND(IsRegEx(A1,"\d+"),NOT(IsRegEx(A1,"[a-zA-Z]")))
    =AND(IsLike(A1,"*#*"),NOT(IsLike(A1,"*[a-zA-Z]*")))
See https://sites.google.com/view/MyExcelToolbox
and https://www.tutorialspoint.com/vbscript/vbscript_reg_expressions.htm

The regular expression [^\d] matches any data that contains a character that is NOT a digit. This can be implemented with a macro:

Function NotDigits(PartNum) As Boolean
Dim regex
Set regex = CreateObject("VBScript.RegExp")
regex.Pattern = "[^\d]"
NotDigits= regex.Test(PartNum)
End Function

Here is a another version of the Tip's DigitsOnly function:

Function DigitsOnly2(Text As String) As Boolean
    DigitsOnly2 = Not Text Like "*[!0123456789 /-]*"
End Function

And here is a more general version that returns TRUE only when a cell's text includes a digit and does not include a letter; Chris might find this more useful:

Function DigitsOnly3(Text As String) As Boolean
    DigitsOnly3 = Text Like "*#*" And Not Text Like "*[a-zA-Z]*"
End Function

My Excel Toolbox includes the following IsLike function for convenient use of VBA's Like operator in a cell formula:

Public Function IsLike(Text As String, Pattern As String) As Boolean
    IsLike = Text Like Pattern
End Function

Therefore, this cell formula matches the result from DigitsOnly2(A1)
    =NOT(IsLike(A1,"*[!0123456789 /-]*"))
and this cell formula matches the result from DigitsOnly3(A1)
    =AND(IsLike(A1,"*#*"),NOT(IsLike(A1,"*[a-zA-Z]*")))
See https://sites.google.com/view/MyExcelToolbox