I've been able to match multiple lines; but only if I know how many lines are coming, and what the content of those lines are...
Select-String -Pattern "^Timestamp: 3/27/2021.*`n`n|^Message:.*errorText:" -Context 2 -LiteralPath .\SomeLog.log
Is there a way to match multiple lines without knowing what is in between?
for instance to match
[START]
...
...
[END]
I read something about changing the settings to the regex with (?sme) but it doesn't seem to work.
I was trying something like the following:
Select-String -Pattern '(sme?)\[START\].*\n(.*\n)\ \[END\]'
CodePudding user response:
To make Select-String
match multiline substrings:
You must provide the input as a single, multiline string, which is what
Get-Content
's-Raw
switch provides.As needed, in the regex passed to
Select-String
's-Pattern
parameter, use inline regex optionm
(multi-line) to make^
and$
match the beginning and end of each line ((?m)
) and/or options
(single-line) to make.
match newline characters ("`n"
) too ((?s)
); you can activate both with(?sm)
.
Here's an example with a multiline here-string serving as input, instead of, say,
Get-Content -Raw file.txt
:
(@'
before
[START]
...1
...2
[END]
after
[START]
...3
...4
[END]
done
'@ |
Select-String -AllMatches -Pattern '(?sm)^\[START\]$. ?^\[END\]$'
).Matches.Value -join "`n------------------------`n"
Note: Strictly speaking, only [
, not also ]
, requires escaping with \
.
If you only want to find the first block of matching lines, omit -AllMatches
.Thanks, Wiktor Stribiżew.
-AllMatches
requests returning all matches per input string, and is normally - with line-by-line input - used to find multiple matches per line. Here, with a multiline input string, all (potentially multiline) matches inside it are returned.
Output:
[START]
...1
...2
[END]
------------------------
[START]
...3
...4
[END]
If you want to return only what is between the delimiter lines:
(@'
before
[START]
...1
...2
[END]
after
[START]
...3
...4
[END]
done
'@ |
Select-String -AllMatches -Pattern '(?sm)^\[START\]\r?\n(.*?)\r?\n\[END\]$'
).Matches.ForEach({ $_.Groups[1].Value }) -join "`n------------------------`n"
Output:
...1
...2
------------------------
...3
...4