Powershell - Trouble With Loops - powershell

Question

First I would like to generate a directory listing for all text files in a directory. Next take each of those text files and get-contents. Then I want to go through the contents and search for all text files in another directory which share contents with the first file and output those corresponding matches to a file named after the source file.
I'm very new at all of this and realize I'm missing some serious fundamental chunks of knowledge. What little scripting experience I have is in Javascript which doesn't seem entirely transferable. (Although programming is programming I'm told.)
This is what I have so far:
$max = get-content h:test1\one.txt | Measure-Object
$A = get-content h:test1\one.txt
For($i=0; $i -lt $max.count ; $i++){
select-string h:test2\*.txt -pattern $($A[$i]) | Format-Table | Out-File ($i + '.txt')
}
I'm hoping for something like:
$max = get-content $files[i] | Measure-Object
$A = get-content files[i]
For($j=0; $j -lt $max.count ; $j++){
select-string h:test2\*.txt -pattern $($A[$j]) | Format-Table | Out-File($files[i].basename + $j + '.txt')
}
Any and all help would be extremely appreciated,
Kurtis
So
Book 1 (one.txt)
The capital of France is Paris.
The population of Paris is twelve.
Book 2 (two.txt)
France is a beautiful country.
The capital of France is Paris.
I basically want a report of the fact that two.txt shares a line with one.txt.

Answer 1

First I would like to generate a directory listing for all text files in a directory
Here's how:
$textFiles1 = dir -Path C:\Books1 -Filter *.txt
$textFiles2 = dir -Path C:\Books2 -Filter *.txt
Next take each of those text files and get-contents.
I want to see whether any lines from the first book are in any of the other books.
Here's an algorithm to do this (untested) (tested):
foreach ($textFile in $textFiles1) {
$lines = get-content -Path $textFile
foreach ($line in $lines) {
foreach ($textFile2 in $textFiles2) {
$lines2 = get-content -Path $textFile2
if ($lines2 -contains $line) {
$matchMessage = 'Line: "{0}" is duplicated in "{1}".' -f $line, $textFile2
$matchMessage | out-file C:\report.txt -encoding UTF8 -Append
}
}
}
}
notepad C:\report.txt

Answer 2

OK let's break this down:
First I would like to generate a directory listing for all text files in a directory. Next take each of those text files and get-contents.
dir *.txt | get-content
Then I want to go through the contents and search for all text files
in another directory which share contents with the first file
OK, now we pipe all that text to select-string (first filtering out all empty string with ?{$_}:
dir *.txt | get-content | ?{$_} | %{select-string -path searchPath\*.txt -pattern "$_" -simple}
and output those corresponding matches to a file named after the
source file.
So now it gets tricky because we have to go back and track our source file name, we do this by wraqpping our query in a foreach (i.e. %{} ):
dir *.txt | %{ $sourceFile = $_; get-content $_ | ?{$_} | %{select-string -path searchPath\*.txt -pattern "$_" -simple} | out-file "$sourceFile.results" }