Filter rows based on condition of certain column - object reference not set to an instance of an object

Help
1

Hi,
Main.xaml (10.9 KB)
Tst.xlsx (23.1 KB)

I have been trying to read this excel file and select certain rows/cells based on condition in column A. In this case, if the value in column A (Apple A) is Z67, get all the values in column C (Citrus) and write them into text file. So I should get CA, CB, CC, CD back.

At this point, I am just trying to get all the records that belongs to Z67. However, I get the error saying the object reference not set blahblah with the workflow that I have in the xaml.

Also, is there a way to select only column A and column C even before I start to create the dataTable? Using if else condition? I think it would be faster and more efficient because I don’t need all other information in that excel - only column A and column C.

I am aware of this site - https://www.uipath.com/kb-articles/how-to-filter-a-data-table

In terms of the forloops as indicated on the website above, why do we need 2 forloops? and what should the TypeArgument be for the second for loop?

Please see attachments and check my xaml. Thanks in advance

2

Hi @lavint,
I have changed a little bit in the code and I have attached the xml here.

File : object reference not set to an instance of an object.zip (17.9 KB)

Regards
Balamurugan

3

Hi @lavint,
The xl source is having the 9 columns. That is the reason you are getting the null error.

image

Regards
Balamurugan

5

Hi Balamurugan,

Thank you so much for your rapid reply. The solution that you provided works well! And my next question is how to print all the result in one setting, i.e., [CA,CB,CC,CD] in a text file in separate lines.

Currently when I write text file, it only shows CD because it is overwriting the text file every time it goes through the for loop. I am thinking to assign a list string above the for loop, then add row into the list for each row. but how can I achieve this? Thanks!

p.s. I removed the forloop, and tried to use output datatable and show the result in the message box but all data are shown instead of just [CA,CB,CC,CD]…

And I tried to put invoke method inside the forloop to add on the empty list variable that I created, but I got "Ststem.Collections.Generic.List’1[System.String] as the result for my message box… Please see attachment

Main.xaml (12.8 KB)

Warm regards,
Lavina

6

Hi @lavint,
Here i have attached the xml for your situation.

File : StringJoin.zip (11.9 KB)

regards
Balamurugan

7

Works perfectly! Learning from your code. Thanks a lot!

1 Like