(Experimental) Scales a Raw ZPL file from 203 DPI (dots per inch) to 300 DPI

scale-zpl.ps1

<#
 # author: Tim Walker
 # date: 2016-11-11
 # original author:  Tres Finocchiaro
 # original date:    2015-05-22
 # license: Public Domain; Use as you wish.
 # original source:  https://gist.github.com/tresf/95f28644669a1e1970a7
 #>


<#
 # Scales all integers found in a designated section
 #>
function scaleSection([string]$cmd, [string]$section, [double]$scaleFactor) {
	[bool]$isInt = $false
	[int]$toInt = 0
	$parts = $section.Substring($cmd.length).Split(',')
	for ($i = 0; $i -lt $parts.Count; $i++) {
		$isInt = [int]::TryParse($parts[$i], [ref]$toInt)
		if ($isInt) {
			$eol = ''
			if ($parts[$i].EndsWith("`r`n")) {
				$eol = "`r`n"
			}
			elseif ($parts[$i].EndsWith("`n")) {
				$eol = "`n"
			}
			elseif ($parts[$i].EndsWith("`r")) {
				$eol = "`r"
			}
		$parts[$i] = ($scaleFactor * $toInt).ToString("000") + $eol
		}
	}
	return $cmd + ($parts -join ',')
}
<#
 # Scales text from a raw ZPL label file from 203 DPI to 300 DPI
 #>
function scaleZPL([string]$inputFile, [double]$scaleFactor = 300/203) {
	$sections = (Get-Content -path $inputFile -Delimiter `0).Split('^')
	
	# ZPL commands to perform conversion on
	$zplmatchcmds = @('FO', 'A[^,]*', 'LL', 'LH', 'GB', 'FB', 'B[^,]*')
	$regexcmds = "^((" + ($zplmatchcmds -join ')|(') + ')).*'
    
	# Can't do foreach here as it creates a copy of the array
	for ($i = 0; $i -lt $sections.Count; $i++) {
		$cmdmatch = $sections[$i] | Select-String -Pattern $regexcmds
		if ($cmdmatch.Matches.Groups.Count -ne 0) {
			$cmd = $cmdmatch.Matches.Groups[1].Value
			$sections[$i] = scaleSection -cmd $cmd -section $sections[$i] -scaleFactor $scaleFactor
		}
	}
	($sections -join '^')
}
# example usage
scaleZPL -inputFile 'c:\myfile.zpl'