How to update an object property located in an array of objects

Question

Hello all,
I have a script that creates custom objects and populates them and saves them into an array. This array of objects is later converted to a CSV file for reuse later on. On a subsequent need to run the script and to save time and avoid recollecting
data I have previously amassed, I read in the contents of the csv file and put this data into an arryOfObjects.
I need to manipulate the data in specific objects but I can't figure out how to accomplish that task.
I can identify the correct object within the array with the following command. I have been trying to pipe that result into either set-variable or set-itemproperty without success.
$arrayOfObjects | select-object | where HostName -like $_.'name'
This works, I can see my desired object and the data fields contained within it.
I now need to modify one of the property fields. (Alias).
I have been trying the following as a line of thought, but so far without success. It doesn't fail/error out, but it doesn't update the data either.
$arrayOfObjects | select-object | where HostName -like $_.'name' | set-itemproperty -name Alias -value "newAlias"
I'm wondering if I need to specify something for the -path argument, but since the array is in memory and not a registry location or a file I am not sure what I should use, if this is the problem at all.
Any suggestions would be appreciated.
Thanks
Smitty

Answer 1

yes, I have redacted things, and obscured other things because I can not go around posting critical infrastructure information out on the internet.
Here is the first three lines of my .csv file
"OrigIP","AL_HostName","AL_Found","AL_Enabled","AL_Status","N_HostName","InREDACTED","N_Found","Delta","IsStale","Ping","InDNS","InAD","Location","Alias","IsServer","HostType","OS","ApplianceName","FQDN","ChatterValue"
"10.24.11.4","ABCD","yes","yes","never","abcd.domain.com","yes","yes","*","*","Y","Y","N","TEST","*","*","eventlog","","","ABCD.DOMAIN.COM","*"
"10.24.12.18","EFGH","yes","yes","Dec 30 2014 09:15:00","efgh.domain.com","yes","yes","-25","No","Y","Y","Y","TEST","*","yes","eventlog","xxxxxx","","EFGH.DOMAIN.COM","*"
When I import this file I create a new custom object (objectCurrent) which I populate with the data from the csv file. I then store this object into an array of objects (objectCollection).
All of the data is present.
I then read in a new csv file that would contain most of the same hosts, but possibly additional new ones. upon importing the second csv file I loop through the entries.
 I have a conditional statement that checks to see if the host name from the second csv file, if it isn't then treat it like a new object and go fill in all of the details of the object using my various functions, etc.
Import-CSV$currentALReport-Delimiter","|ForEach-Object
     if($objectCollection.N_HostName
-notcontains$_.'name')
        # then create a new currentObject and go populate the properties of the object 
     elseif ($objectCollection.N_HostName -contains $_.'name') {
          # copy this object and update the object's AL_Status (which is the last reported message date info)
              # send that to the function that will parse it, compare Julian dates and see if it falls within my
              # criteria as being stale.  if so set the IsStale property to Yes, but reguardless set the AL_Status
              # newest last reported message data
JRV states that "The "select object" does nothing at all unless you have a column in your CSV called "object".  The where clause will do nothing because it is syntatctically wrong and illogical. "
I beg to differ.  Using the above command :   with the script running and the current focus ($_.'name') equals "abcd.domain.com"
 $arrayOfObjects | select-object | where N_HostName -like $_.'name'
It obtain a single object within my array of objects similar to this:
IP: 1.2.3.4
N_HostName: abcd.domain.com
IsStale: No
LastMsgDate: Dec 30 2014 09:15:00
Delta: 1
Ping: Yes
InDNS: Yes
InAD: Yes
Alias: *
(other fields omitted for brevity) I could get any of my existing objects if I match the hostname
If I used only the command "  $objectCollection | Select-Object "    it returns every object in my array.
So to narrow down the selection to a single object I add the " | where N_HostName -like $_.'name'  "
which gives me the exact object I am searching for.
My only question is how can I modify the contents of the object that I have specified within the array of object???