Extract Lines between two patterns using Powershell

I have a text file which I need to extract a undefined number of rows. However, I have a patterns for both the start and end index.

• The Start Index is flagged by two consecutive rows. First being "LOAD SUMMARY" and the second being "============"
• The end index is flagged by the row that contains ***** END LOAD SESSION *****

I then need these indexes offet by 2 rows (upwards)/ Let say the TXT file contains this

maybe some more text

some text

SOme really important text LOAD SUMMARY. But I don't want to include this row. 

023-03-06 13:57:55.719 <TASK_12836-WRITER_2_*_1> INFO: [WRT_8035] Load complete time: Mon Mar 06 13:57:55 2023

LOAD SUMMARY
============


WRT_8036 Target: MAPPING NAME (Instance Name: [MAPPING NAME])

WRT_8038 Inserted rows - Requested: 45147                Applied: 45147                Rejected: 0                    Affected: 45147              

2023-03-06 13:57:55.719 <TASK_12836-WRITER_2_*_1> INFO: [WRT_8043] *****END LOAD SESSION*****

SOme more test 

LOAD SUMMARY > I don't want this row either

I want the $extractedlines variable to return this

023-03-06 13:57:55.719 <TASK_12836-WRITER_2_*_1> INFO: [WRT_8035] Load complete time: Mon Mar 06 13:57:55 2023

LOAD SUMMARY
============


WRT_8036 Target: MAPPING NAME (Instance Name: [MAPPING NAME])

WRT_8038 Inserted rows - Requested: 45147                Applied: 45147                Rejected: 0                    Affected: 45147              

This is my code so far

# Specify the path to the file you want to extract lines from
$file = "C:\Users\YOURNAME\Desktop\Load Summary.txt"

# Get the contents of the file as an array of strings
$content = Get-Content $file

# Find the line number of the first occurrence of "LOAD SUMMARY"
$startIndex = ($content | Select-String -Pattern "LOAD SUMMARY").LineNumber

# Find the line number of the first occurrence of "*****END LOAD SESSION*****"
$endIndex = ($content | Select-String -Pattern "\*\*\*\*\*END LOAD SESSION\*\*\*\*\*").LineNumber - 1

# Iterate through the lines between the start and end indices to find the "============" line
for ($i = $startIndex; $i -le $endIndex; $i++) {
    if ($content[$i] -eq "============") {
        # If the "============" line is found, set the start index to the next line
        $startIndex = $i + 1
        break
    }
}
$startIndex = [int]$startIndex
$endIndex = [int]$endIndex

# Extract the lines between the start and end indices
$extractedLines = $content[$startIndex..$endIndex]

# Output the extracted lines
$extractedLines

This might help you get started, since you're looking to match 2 lines above the start index then the easiest way is to hold the content of the file in memory before processing it. See the inline comments to help you with the logic.

# define how many lines before matching `$start`
$offset = 2
# these are the 2 lines that signal to start capturing
$start = @(
    'LOAD SUMMARY'
    '============'
)

# this one signals to break the loop
$finish = '*****END LOAD SESSION*****'

# read the file content
$content = Get-Content "C:\Users\YOURNAME\Desktop\Load Summary.txt"

$startCapture = $false
$extractedLines = for($i = 0; $i -lt $content.Length; $i++) {
    # if this line matches the index 0 of the `$start` array and
    # the next line matches the index 1
    if($content[$i] -like "*$($start[0])*" -and $content[$i + 1] -like "*$($start[1])*") {
        # then, set this boolean to signal start capturing the following lines
        $startCapture = $true
        # output from this line minus the offset (2 lines above in this case)
        # up to this line and next line
        $content[($i - $offset)..($i + 1)]
        # increment `$i` so we don't check the next line (already did here!)
        $i++
        # and continue with the next loop iteration,
        # we don't want below conditions to be evaluated in this case
        continue
    }

    # if this line matches the string singaling to stop capture
    if($content[$i] -like "*$finish*") {
        # break the loop
        break
    }

    # if the first condition was true then
    if($startCapture) {
        # output this line as-is
        $content[$i]
    }
}

# here is the result
$extractedLines

If all you really need are the selected lines, you can capture them with a single regex:

$file = 'C:\Users\YOURNAME\Desktop\Load Summary.txt'

$pattern = '(?s)([^\n\r]*\r?\n){2}LOAD SUMMARY\r?\n={12}(\r?\n[^\n\r]*)*?\r?\n(?=[^\n\r]*\*{5}END LOAD SESSION\*{5})'

$extractedLines = [Regex]::Match( (Get-Content $file -Raw) , $pattern ).Value

$extractedLines

• (?s) : Single-line mode (DOTALL)
• ([^\n\r]*\r?\n){2} : (&lt;Zero or more non-linebreak characters><NewLine&gt;) × 2
• LOAD SUMMARY\r?\n={12} : Literal two-line match
• (\r?\n[^\n\r]*)*? : Zero or more (lazy) (&lt;NewLine>&lt;Zero or more non-linebreak characters>)
• \r?\n : Final newline
• (?=[^\n\r]*\*{5}END LOAD SESSION\*{5}) : Positive lookahead (not captured)