Find anything but a number or "C" - vba

Question

I have this formula (below) where I am trying to find a space in C1. Instead of this, I would like to update this formula to look for anything except for "C" or any number and not only find a space.
LEFT(C1, find("" "", C1, 1)-1)
For e.g.
if C1 has - "C1234 - XXX" or "C1234-XXX" or "C1234:XXX", I always want the above function to find anything except for "C" and "1234" (i.e. numbers).
P.S.: I would want to use the find function only with improvements to meet the above conditions.
Please suggest.

Answer 1

Perhaps this:
'To create a new string from a source string which will or will not contain the characters present within the source string
'Examples of string of characters: 0123456789 -OR- {}[]<>\/|+*=-_(),.:;?!##$%^&™®©~'" OR - combination of various characters
Public Function getNewStringFromString(ByVal strSource As Variant, ByVal strChars As Variant, Optional isInString As Boolean = True) As String
Dim strArr As Variant, iChar As Variant
getNewStringFromString = ""
If VarType(strSource) = vbString And VarType(strChars) = vbString Then
strSource = Trim(strSource): strChars = Trim(strChars)
If Len(strSource) > 0 And Len(strChars) > 0 Then
strArr = Split(StrConv(strSource, vbUnicode), vbNullChar)
For Each iChar In strArr
If (isInString Xor isInArray(iChar, strChars)) = False Then getNewStringFromString = getNewStringFromString + iChar
Next iChar
Erase strArr
End If
End If
End Function
Use as the following:
MsgBox getNewStringFromString(CStr(Range("C1")), "C0123456789")
Forgot to give you the code for the isInArray function. Here it is:
'To check if an element is within a specific Array, Object, Range, String, etc.
Public Function isInArray(ByVal itemSearched As Variant, ByVal aArray As Variant) As Boolean
Dim item As Variant
If VarType(aArray) >= vbArray Or VarType(aArray) = vbObject Or VarType(aArray) = vbDataObject Or TypeName(aArray) = "Range" Then
For Each item In aArray
If itemSearched = item Then
isInArray = True
Exit Function
End If
Next item
isInArray = False
ElseIf VarType(aArray) = vbString Then
isInArray = InStr(1, aArray, itemSearched, vbBinaryCompare) > 0 'Comparing character by character
Else
On Error Resume Next
isInArray = Not IsError(Application.Match(itemSearched, aArray, False))
Err.Clear: On Error GoTo 0
End If
End Function

Answer 2

Given your data format, where
C is always the first character
subsequent values are all digits
You want to return the C followed by the digits
Try:
="C" & LOOKUP(9E+307,VALUE(MID(A1,2,{1,2,3,4,5,6,7})))
If there might be more than 7 digits, you can either extend the array constant, or use a formula to create a larger array.
The formula looks for the largest integer in the string, starting with position 2. So it will stop at the last non-digit, since anything including a non-digit will return an error.
If the "non-digit" might be your decimal or thousands separator, you will need to replace it with something else, with a nested SUBSTITUTE
Replace . , and space with -
=LOOKUP(1E+307,--SUBSTITUTE(SUBSTITUTE(SUBSTITUTE(MID(A1,2,{1,2,3,4,5,6,7}),",","-"),".","-"),".","-"))
For a VBA solution, I would use regular expressions.
Option Explicit
Function getCnum(str As String)
Dim RE As Object
Const sPat As String = "(^C\d+).*"
Set RE = CreateObject("vbscript.regexp")
With RE
.Global = False
.MultiLine = True
.ignorecase = True
.Pattern = sPat
getCnum = .Replace(str, "$1")
End With
End Function
Note that this also validates the string by checking that the first letter is, in fact, a C (or c). If you want it to be case-sensitive, make the obvious change.