5 if statement formula - vba

Question

I recently created an IF formula to run inside a macro for only 2 statements but I need to add 3 more to it.
This is for altering a filename. So I use the LEN to determine what type of file it is then run the appropriate formula to trim out what I don't want.
Examples:
173d0221.pdf = S-173-D022 Description.pdf
=CHAR(83)&CHAR(45)&LEFT(B11,LEN(B11)-9)&CHAR(45)&UPPER(MID(B11,4,LEN(B11)-8))&CHAR(32)&D11&E11
173d02210.pdf = S-173-D022 Description.pdf =CHAR(83)&CHAR(45)&LEFT(B12,LEN(B12)-10)&CHAR(45)&UPPER(MID(B12,4,LEN(B12)-9))&CHAR(32)&D12&E12
173d170c141.pdf = SD-170-C14 Description.pdf
=CHAR(83)&CHAR(68)&CHAR(45)&UPPER(MID(B13,5,LEN(B13)-12))&CHAR(45)&UPPER(MID(B13,8,LEN(B13)-12)&CHAR(32)&D13&E13)
REF-173d0221.pdf = REF-173-D022 Description.pdf
=LEFT(B14,LEN(B14)-9)&CHAR(45)&UPPER(MID(B14,8,LEN(B14)-12))&CHAR(32)&D14&E14
REF-173d02210.pdf = REF-173-D022 Description.pdf
=LEFT(B15,LEN(B15)-10)&CHAR(45)&UPPER(MID(B15,8,LEN(B15)-13))&CHAR(32)&D15&E15
I am having trouble linking them together to get it to apply the right formula based on the length of the cell.
Notes: I am using CHAR(83)&CHAR(45) instead of "S-" because VBA wasn't liking the text. I will update the "B12" cell tag with " & aCell & " once everything is working smoothly.
My vba code looks like:
.Range("C2:C" & LastRow).Formula = "=IF(LEN(" & aCell & ")=12,CHAR(83)&CHAR(45)&LEFT(" & aCell & ",LEN(" & aCell & ")-9)&CHAR(45)&UPPER(MID(" & aCell & ",4,LEN(" & aCell & ")-8))&CHAR(32)&" & dCell & "&" & eCell & ",LEFT(" & aCell & ",LEN(" & aCell & ")-9)&CHAR(45)&UPPER(MID(" & aCell & ",8,LEN(" & aCell & ")-12))&CHAR(32)&" & dCell & "&" & eCell & ")"

Answer 1

This seems to work for the first three example formula.
I'll leave it to you to translate the remaining 2 formula to VBA, which you should be able to do following my examples :)
Option Explicit
Sub foo()
Dim rng As Range, aCell As Range
Dim val As String
Set rng = Range("B1:B5") '## Modify the input range as needed.
For Each aCell In rng.Cells
Select Case Len(aCell)
Case 12
val = "S-" & Left(aCell, Len(aCell) - 9) & "-" & Mid(aCell, 4, Len(aCell) - 8)
Case 13
val = "S-" & Left(aCell, Len(aCell) - 10) & "-" & Mid(aCell, 4, Len(aCell) - 9)
Case 15
val = "SD-" & Mid(aCell, 5, Len(aCell) - 12) & "-" & Mid(aCell, 8, Len(aCell) - 12)
Case 16
val = "REF-" '## Modify as needed
Case 17
val = "REF-" '## Modify as needed
Case Else
'maybe warn the user this input is not anticipated...
MsgBox "Unsupported length!", vbInformation
End Select
val = UCase(val)
'## Append the values from column D,E:
val = val & " " & aCell.Offset(, 2) & aCell.Offset(, 3)
'## Write out to the workbook in column F, modify the "5" to specify a different location if needed e.g., "-1" would put it in column A, "0" would put in same column B, etc.
aCell.Offset(, 4).Value = val
Next
End Sub