I want to append a new column into Excel

Hi all,
I am new to UiPath. I want to append a new column to the very end, and the value of the new column is using the numbers in the existing column (column header name is “ValidatedDistance”) multiple $65.5 (e.g. 19.2 * 65.5 = 1257.6). I want numbers like 1257.6 in the new column. Can anyone help me with that? Thanks!


Hi @Mengdi_Wei, welcome to the Community.

You can use the following query in the Invoke Code activity:

row("New Col") = CInt(Row("ValidatedDistance").ToString) * 65.5
End Sub)


Edit: The ‘Argument’ values for Invoke Code -

Hope this helps,
Best Regards.


Welcome to the community

You can use as below…

  1. Use add data column to add a new data column to the existing datatable if column is not already present
  2. Then use expression to perform this using a assign activity dt.Columns("DeductableCost").Expression = "65.5 * [ValidatedColumn]"



You can use Add Data Column activity
After that, you can use For Each Row and in Properties declare a variable as Index

So, to fill the column you can use Assign activity and write as below

dt_validated.Rows(Index).Item(“StandardMileage”) =Cint(row(“StandardMilege”).ToString) * 65.5

Hope this may help you


Hi @BlueBird1
IF youwanna Multiply one column with your value u can follow this simple.

Step:1 Add Datacolumn (which u wanna toadd in the Table)
Step:1 drag Assign Activity
Left Side:


Value side


here attached Xaml
test.zip (69.5 KB)


It shows an error like the image, I can’t understand why the error is


Can you please replace the "(Quotations) correctly, you have copied and pasted the expression that where it was bit different


Thanks, but for some reason, I couldn’t open the workflow after I downloaded it. I tried using the step you said, but it runs an error on my workflow.

Not quite sure what should I do, but I replace the code you said before


The standard milege should be double type

also please open the locals panel and check the error details from there…it would give more info

Did you use expression like this ?


DT_validated.Columns(“DeductableCost”).Expression = “[ValidatedDistance]*65.5”

I used this one above. Sorry I am not majoring in CS, I don’t know how to open the locals panel.

Now I assign the standard mileage rate to double type, but I don’t know if I should continue to use the “standardMileageRate2023” variable, it seems like if I just use the equation “[ValidatedDistance]*65.5” there is no need to assign a special variable.


If you use 65.5 firectly yes you need not use it

Run the bot in debug mode…and when error comes …on the left side you would see locals panel just like activities projects etc…open that and check the error

Even if you use 65.5 directly you are getting the error?

If possible please share input excel and/or the xaml you are using



It will definitely work.
Inside the Assign Activity

Just Copy and Paste the expression below in the Assign Acivity

Left Side:


Note: DT = Your Datatable

Righ Side:


Note: Column1= Which column u want to multiply with 65.5.


Mini Bot Test.zip (71.9 KB)
Here is the input excel (actually the one in the output folder named “validated”)and the xaml I am working on.
I am stuck on the “Test Sequence”.


Thanks, VP, but my professor doesn’t recommend I use the expression since we did not learn this before. I really stuck on how to use this expression.

Hi all,
I found a way to solve my “append a new column” question. Thank you all for helping me.
Now, I meet a new question about filter data table, I wonder if anyone of you can help me with that.

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