How do parse this string in Powershell? - regex

Question

I have a block of text I need to parse (saved in a variable) but I'm unsure how to go about it. This block of text, saved in a variable we can call $block for simplicity's sake, includes all the whitespace shown below.
I would like the result to be an iterable list, the first value being Health_AEPOEP_Membership_Summary - Dev and the second one being Health_AEPOEP_YoY_Comparison_Summary - Dev. Assume this list of workbooks can be longer (up to 50) or shorter (minimum 1 workbook), and all workbooks are formatted similarly (in terms of name_with_underscores - Dev. I'd try the $block.split(" ") method, but this method gives many spaces which may be hard to enumerate and account for.
Workbooks : Health_AEPOEP_Membership_Summary - Dev [Project: Health - Dev]
Health_AEPOEP_YoY_Comparison_Summary - Dev [Project: Health - Dev]
Any help is much appreciated!

Answer 1

You could write a multi-line regex pattern and try to extract the names, but it might be easier to reason about if you just breaking it into simple(r) steps:
$string = #'
Workbooks : Health_AEPOEP_Membership_Summary - Dev [Project: Health - Dev]
Health_AEPOEP_YoY_Comparison_Summary - Dev [Project: Health - Dev]
'#
# Split into one string per line
$strings = $string -split '\r?\n'
# Remove leading whitespace
$strings = $strings -replace '^\s*'
# Remove `Workbooks : ` prefix (strings that don't match will be left untouched)
$strings = $strings -replace '^Workbooks :\s*'
# Remove `[Project $NAME]` suffix
$strings = $strings -replace '\s*\[Project: [^\]]+\]'
# Get rid of empty lines
$strings = $strings |Where-Object Length
$strings now contains the two project names

Answer 2

If the text is in a file it would make this a little easier, and I would recommend this approach
switch -Regex -file ($file){
'(\w+_.+- Dev)' {$matches.1}
}
Regex details
() - capture group
\w+ - match one or more letter characters
_ - match literal underscore
.+ - match one or more of any character
- Dev - literal match of dash space Dev
If it's already in a variable, it would depend if it's a string array or a single string. Assuming it's a single string, I'd recommend this approach
$regex = [regex]'(\w+_.+)(?=(\s\[.+))'
$regex.Matches($block).value
Health_AEPOEP_Membership_Summary - Dev
Health_AEPOEP_YoY_Comparison_Summary - Dev
Regex details
Same as above but added the following
(?=) - Look ahead
\s\[.+ - match a space, a left square bracket, one or more characters
Simply add a variable assignment $strings = before either of these to capture the output. Either would work on one or 500 workbooks.