Splitting Texts by Fixed Width

Let’s assume you need to split a text using a fixed width. For example, if you needed the first 5 character of a text, plus the remainder, how would you do this?

Most PowerShell users would probably use string methods like these:

$text = 'ID12:Here is the text'
$prefix = $text.Substring(0,5)
$suffix = $text.Substring(5)
$prefix
$suffix

Of course, if you had a split character such as “:”, you could also go with this:

$prefix, $suffix = 'ID12:Here is the text' -split ':'
$prefix
$suffix 

However, this would consume the split character plus it can produce more than two parts. And it is not what the job was: to split a text using a fixed WIDTH. Yet you still can use the -split operator:

$prefix, $suffix = 'ID12:Here is the text' -split '(?<=^.{5})'
$prefix
$suffix  

The regex construct “(?<=XXX)” is a so-called “look behind” and not consumed. “^” represents the text start, and “.” represents any character. As you may have guessed, “{5}” qualifies how often the placeholder must occur, so essentially this regex splits the first 5 characters from the rest of the text and always returns two chunks (provided the text is at least 6 characters long).


psconf.eu – PowerShell Conference EU 2019 – June 4-7, Hannover Germany – visit www.psconf.eu There aren’t too many trainings around for experienced PowerShell scripters where you really still learn something new. But there’s one place you don’t want to miss: PowerShell Conference EU – with 40 renown international speakers including PowerShell team members and MVPs, plus 350 professional and creative PowerShell scripters. Registration is open at www.psconf.eu, and the full 3-track 4-days agenda becomes available soon. Once a year it’s just a smart move to come together, update know-how, learn about security and mitigations, and bring home fresh ideas and authoritative guidance. We’d sure love to see and hear from you!

Twitter This Tip! ReTweet this Tip!

GD Star Rating
loading...