I'm stuck with my script. I need to compare two arrays, one is the result of a query, the other one of a content of a file:
$Array1 = Invoke-Sqlcmd -Query "select name from person"
$Array2 = Get-Content ".\Myfile.txt" #the file is a set of one item
every line
Now, in $Array2 there are items that I would like to delete from the $Array1.
How can I do this? Thank you for yr help!
Use the Where-Object cmdlet to filter $Array1 based on what is in $Array2:
$Array1 = @($Array1 |Where-Object { $Array2 -notcontains $_ })
That works if Invoke-Sqlcmd returns simple strings. If not, you could do something like:
$Array1 = @($Array1 |Where-Object { $Array2 -notcontains $_.someProperty })
If performance is an issue, you can get faster results constructing an alternating regex from one of the arrays, and using it as an array operator against the other.
$Array1 = Invoke-Sqlcmd -Query "select name from person"
$Array2 = Get-Content ".\Myfile.txt" #the file is a set of one item
every line
$regex = ‘(?i)^(‘ + (($Array2 |foreach {[regex]::escape($_)}) –join “|”) + ‘)$’
$Array1 -notmatch $regex
Explanation of the code to build the regex here.
Or with an arraylist, there's a Remove (or RemoveAt) method (case sensitive):
$array2 = 1,2,3
[collections.arraylist]$array = 1,2,3,4,5,6
$array2 | % { $array.remove($_) }
$array
4
5
6
