Notepad++ regex to extract usernames from this list - regex

Question

I have this list below:
scrapeDate,username,full_name,is_private,follower_count,following_count,media_count,biography,hasProfilePic,external_url,email,contact_phone_number,address_street,category,businessJoinDate,businessCountry,businessAds,countryCode,cityName,isverified
07/05/2020 05:37 AM,maplethenorwich,Maple the Norwich,False,0,0,0,,False,,,,,,,,,,,No
07/05/2020 05:37 AM,baby_yoda_militia,Baby Yoda,False,0,0,0,,False,,,,,,,,,,,No
07/05/2020 05:37 AM,caciquegoldendoodle,CaciqueGoldenDoodle,False,0,0,0,,False,,,,,,,,,,,No
07/05/2020 05:37 AM,ja_watts,Julie Anna Watts,False,0,0,0,,False,,,,,,,,,,,No
07/05/2020 05:37 AM,lets_go_zumba_and_travel,Mrsirenetakamoto,False,0,0,0,,False,,,,,,,,,,,No
07/05/2020 05:37 AM,bunnyslash,Bunnyslash,False,0,0,0,,False,,,,,,,,,,,No
I would like to get the Usernames only as below:
maplethenorwich
baby_yoda_militia
caciquegoldendoodle
ja_watts
lets_go_zumba_and_travel
bunnyslash
I've tried ^(?:[^,\r\n]*,){3}([^,\r\n]+).* but it gets me "False".
I wish somebody who can help me to find the right Regex to extract the Usernames only.

Answer 1

You may try:
.*?,(.*?),.*
Explanation of the above regex:
.*? - Lazily matches everything except the new line.
, - Matches , literally.
(.*?) - Represents first capturing group matching lazily username or the second values in csv.
,.* - Greedily matching everything except new line. If you don't want to remove the contents; just leave this and capture the above group and write them to a new file or according to your requirement.
$1 - For the replacement part replace all the matched text with just the captured group using $1.
You can find the demo of the above regex in here.
Result Snap from notepad++

Answer 2

You are repeating the group 3 times using quantifier {3}, but there is no need to repeat it because you want the second value.
^(?:[^,\r\n]*,){3}([^,\r\n]+).*
^^^ ^^^^
You can omit the quantifier and the non capturing group as there is nothing to repeat.
^[^,\r\n]*,([^,\r\n]+).*
^ Start of the string
[^,\r\n]*, Match 0+ times any char except a comma or newline, then match ,
( Capture group 1
[^,\r\n]+ Match 1+ times any char except a comma or newline
) Close group 1
.* Match the rest of the line
Regex demo