Question

I have a powershell script in which I do the following

$somePSObjectHashtables = New-Object Hashtable[] $somePSObject.Length;
$somePSObjects = Import-CSV $csvPath
0..($somePSObject.Length - 1) | ForEach-Object {
    $i = $_;
    $somePSObjectHashtables[$i] = @{};
    $somePSObject[$_].PSObject.Properties | ForEach-Object {
        $somePSObjectHashtables[$i][$_.Name] = $_.Value;
    }
}

I need to do this because I want to make several distinct copies of the data in the CSV to perform several distinct manipulations. In a sense I’m performing an “INNER JOIN” on the resulting array of PSObject. I can easily iterate through $somePSObjectHashtables with a ForEach-Object and call Hashtable.Clone() on each member of the array. I can then use New-Object PSObject -Property $someHashTable[$i] to get a deep copy of the PSObject.

My question is, is there some easier way of making the deep copy, without an intermediary Hashtable?

Answer 1

For getting really deep copies we can use binary serialization (assuming that all data are serializable; this is definitely the case for data that come from CSV):

# Get original data
$data = Import-Csv ...

# Serialize and Deserialize data using BinaryFormatter
$ms = New-Object System.IO.MemoryStream
$bf = New-Object System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
$bf.Serialize($ms, $data)
$ms.Position = 0
$data2 = $bf.Deserialize($ms)
$ms.Close()

# Use deep copied data
$data2