Merging hashtables in PowerShell: how?

Question

I am trying to merge two hashtables, overwriting key-value pairs in the first if the same key exists in the second.

To do this I wrote this function which first remo

Answer 1

To 'inherit' key-values from parent hashtable ($htOld) to child hashtables($htNew), without modifying values of already existing keys in the child hashtables,

function MergeHashtable($htOld, $htNew)
{
    $htOld.Keys | %{
        if (!$htNew.ContainsKey($_)) {
            $htNew[$_] = $htOld[$_];
        }
    }
    return $htNew;
}

Please note that this will modify the $htNew object.