PowerShell Regex with csv file - regex

Question

I'm currently trying to match a pattern of IDs and replace with 0 or 1.
example pc0045601234 replace with 1234 the last 4 and add the 3rd digit in front "01234"
I tried the code below but the out only filled the userid column with No matching employee
$reportPath = '.\report.csv'`$reportPath = '.\report.csv'`
$csvPath = '.\output.csv'
$data = Import-Csv -Path $reportPath
$output = #()
foreach ($row in $data) {
$table = "" | Select ID,FirstName,LastName,userid
$table.ID = $row.ID
$table.FirstName = $row.FirstName
$table.LastName = $row.LastName
switch -Wildcard ($row.ID)
{
{$row.ID -match 'P\d\d\d\d\d\D\D\D'} {$table.userid = "Contractor"; continue}
{$row.ID -match 'SEC\d\d\d\D\D\D\D'} {$table.userid = "Contractor"; continue}
{$row.ID.StartsWith("P005700477")} {$table.userid = $row.ID -replace "P005700477","0477"; continue}
{$row.ID.StartsWith("P00570")} {$table.userid = $row.ID -replace "P00570","0"; continue}
default {$table.userid = "No Matching Employee"}
}
$output += $table
}
$output | Export-csv -NoTypeInformation -Path $csvPath

Answer 1

Here are three different ways to achieve the desired result. The first two use the same technique, just written in a different way.
First we put the sample data in a variable as a multiline string array. This is the equivalent as $text = Get-Content $somefile
$text = #'
PC05601234
PC15601234
'# -split [environment]::NewLine
Option 1 # convert to character array, select the 3rd and last 4 digits.
$text | foreach {-join ($_.ToChararray()| select -Skip 2 -First 1 -Last 4)}
Option 2 # same as above, requiring an extra -join to avoid spaces.
$text | foreach {(-join $_.ToChararray()| foreach{$_[2]+(-join $_[-4..-1])})}
Option 3 # my preference, regex. Capture the desired digits and replace the entire string with those two captured values.
$text -replace '^\D+(?!=\d)(\d)\w+([\d]{4}$)','$1$2'
All of these output
01234
11234
Further testing with different char/digit combinations and lengths.
$text = #'
PC05601234
PC15601234
PC0ABC124321
PC1DE4321
PC0A5678
PC1ABCD215678
'# -split [environment]::NewLine
Running the new sample data through each option all produce this output
01234
11234
04321
14321
05678
15678