Renaming files by reformatting existing filenames - placeholders in replacement strings used with the -replace operator

Question

I have a few video file like this: VideoName_s01e01.mp4 where the season and episodes are variables. I want to add an underscore (\"_\") between the s??

Answer 1

I highly recommend regex101.com for learning regex.

Something like this can work:

"VideoName_s01e01.mp4" -replace '(.*s)(\d+)(e.*)', '$1$2_$3'

Gives:

VideoName_s01_e01.mp4