How to reverse comma separated string in Excel? - excel

Question

How can I use a formula in MS Excel to reverse a comma separated sting in row? The number of values are not always same so some rows have 3, 4 and some only one element.
So the output looks like following image

Answer 1

If you have Office 365 Excel then use This array formula:
=TEXTJOIN(",",,TRIM(MID(SUBSTITUTE(A2,",",REPT(" ",99)),((LEN(A2)-LEN(SUBSTITUTE(A2,",",""))+1)-ROW($XFD$1:INDEX(XFD:XFD,LEN(A2)-LEN(SUBSTITUTE(A2,",",""))+1)))*99+1,99)))
Being an array formula it needs to be confirmed with Ctrl-Shift-Enter instead of Enter when exiting edit mode.
If one does not have Office 365 Excel then vba will probably be the only choice.

Answer 2

Sloppy UDF solution:
Function REVERSESTRING(original As Range, delim As String)
Dim i As Long, reversed As String, arr As Variant
arr = Split(original.Value, delim)
For i = UBound(arr) To 0 Step -1
reversed = reversed & arr(i) & ","
Next i
REVERSESTRING = Left(reversed, Len(reversed) - 1)
End Function

Answer 3

A pure single-cell formula works in Excel 365; with that version there is no need for special array calculation entry, VBscripts, or helper columns:
Procedure
Make the following table in Excel:
Add column headings
Select headings, and press the Table icon on the Insert ribbon tab
Copy formula 1 & 2 below into the appropriate columns
Original | # | Reversed
---------+-----+-----------
| {1} | {2}
Place the string you would like to reverse in the first column.
Details and customization
'Original' column
(holds the delimited string value you wish to process)
Place your source data in this column (as seen in the example images)
'#' column
(counts number of items in delimited cell)
Note: (this column is completely optional; it simply shows the number of items in the original column)
{1} <- replace with formula #1:
=LET(
existingDelimiter, ","
, originalValue, [#[Original]]
, SUM(
LEN(originalValue)
- LEN(
SUBSTITUTE(
originalValue
, existingDelimiter
, ""
)
)
)
+1
)
(Note: If your list uses a delimiter other than a comma or if the first column of your table will have a different name, edit the above as appropriate using the same instructions given for formula #2 below.)
'Reversed' column
(reverses order of delimited items in list; optionally changes delimiter)
{2} <- replace with formula #2:
=LET(
existingDelimiter, ","
, newDelimiter, ","
, originalValue, [#[Original]]
, SUBSTITUTE(
ARRAYTOTEXT(
LET(
list,
IFERROR(
FILTERXML(
"<t><s>"
& SUBSTITUTE(
originalValue
,existingDelimiter
,"</s><s>"
)
& "</s></t>"
, "//s"
)
,""
)
,SORTBY(
list,
SEQUENCE(
ROWS(list)
,1
,ROWS(list)
,-1
)
)
)
,0
)
, ", "
, newDelimiter
)
)
Adjust the formula for what you are trying to accomplish by changing the values for existingDelimiter, newDelimiter, and originalValue, as necessary.
A. To reverse a comma-separated string, use the formula as written:
existingDelimiter, ","
, newDelimiter, ","
Example:
B. To reverse DNS names, replace the comma with a period in the definitions for existingDelimiter and newDelimiter:
existingDelimiter, "."
, newDelimiter, "."
This can be very useful for reverse DNS names (aka Java class names / Universal Type Indicators (UTIs) / etc.)
Example:
Replace "Original" in [#[Original]] with the name of your first column, if different.
A. If using just a single cell for input instead of a table column, replace [#[Original]] with the reference to that cell (e.g. B2):
, originalValue, B2
Example:
Explaination of the "Reversed" column formula:
By manually converting to XML, we can use the FilterXML function, which converts the data to an array.
Having the data in an array allows the use of the SortBy function.
SortBy reverses the array by using a helper array created with the Sequence function.
Finally, the ArrayToText functions converts this (now reverse-ordered) array back to a text string that will fit in a single spreadsheet cell.
This is what allows us not to need a loop, helper columns, or VBScript.
Bonus column
To extract a specific term from a list, use the following formula in another table column:
(Change the number in termNumber to the desired value):
=LET(
existingDelimiter, ","
, originalValue, [#[Original]]
, termNumber, "[2]"
, IFERROR(
FILTERXML(
"<t><s>"
& SUBSTITUTE(
originalValue
, existingDelimiter
, "</s><s>"
)
& "</s></t>"
, "//s"
& termNumber
)
, ""
)
)
Example:
Other notes
Needed:
Excel 365 (for at least FilterXML and Let functions, and dynamic arrays) (*)
It might work with other versions but I have not tested those. Please note in the comments if you notice other or future versions (e.g. Excel 2022) work with this.
Not needed:
dynamic array entry
VBscript
macro-enabled files
(*) This can be done without the Let function, but using Let allows the calculation to be edited / repurposed with less chance for user error.
Note: When the Lambda function is released (hopefully later in 2021) then this all can be wrapped up in a named worksheet function
Bonus: to edit more complex Excel formulas with code highlighting (and other features such as auto-intents and folding), try a text editor with Swift programming language support. Examples:
VSCode editor (free; cross-platform)
Until there is an Excel-specific extension available, install a Swift VSCode extension such as this: Swift language VSCode extension (it seems to work quite well to provide code highlighting and folding)
Notepad++ (free; Windows-only)
Select "Swift" from the "Language" menu
Inspired by (apologies if I've forgotten someone):
https://www.howtoexcel.org/tutorials/split-text-by-delimiter/
https://www.sumproduct.com/news/article/have-you-got-what-it-text-introducing-arraytotext-and-valuetotext
https://exceljet.net/formula/reverse-a-list-or-range