Add row to column to CSV from variable list - list

Question

I've been fighting for over an hour for something that seems simple to me ... But I can not do it
Explanation :
I import a CSV who look like this, he's empty :
DAYS | PC1 | PC2
And i have a Variable "$Days" who look like this :
PS C:\Users> $Days
12/02/2019
13/02/2019
14/02/2019
15/02/2019
16/02/2019
All i want is to add every line to the "Days" column...
Like :
DAYS | PC1 | PC2
12/02/2019 | |
13/02/2019 | |
14/02/2019 | |
15/02/2019 | |
16/02/2019 | |
I try something like :
Foreach ($row in $Days){
$CSV.Days = $row
}
But he tell me that the property "Days" is not found.
i also try something like this :
$CSV | Select-Object #{Name='Days';Expression={$forearch ($row in $Days){$row}}},*
But no result again, i don't know what i'm doing wrong...
Thank you in advance for your help.

Answer 1

The problem with your approach is that the file is empty thus no properties are generated for $CSV
A simple solution is generating the $CSV by iterating $Days and building a [PSCustomObject]
$Days = #'
12/02/2019
13/02/2019
14/02/2019
15/02/2019
16/02/2019
'# -split '\r?\n'
$CSV = $Days | ForEach-Object{
[PSCustomObject]#{
DAYS = $_
PC1 = $NULL
PC2 = $NULL
}
}
$CSV
$CSV | Export-Csv .\YouNameIt.csv -NoTypeInformation

Answer 2

Or, a shorter version:
$CSV-out = $csv | ForEach-Object{[PSCustomObject]#{DAYS = $_}}|Select days, PC1, PC2
$csv is a list of values. Similar to
$csv = #("12/02/2019","13/02/2019","14/02/2019","15/02/2019","16/02/2019")
If you then do a $CSV | FT
DAYS PC1 PC2
---- --- ---
12/02/2019
13/02/2019
14/02/2019
15/02/2019
16/02/2019
You don't have to include a custom object just to add fields. You can do a
select
and it will add them for you as well.