switch statement to calc dates from Import-CSV

by Apr 18, 2017

I am trying to learn the switch statement, and I'm missing some basics.

For a collection imported from CSV, I want to determine for each row a date in the past, using Get-Date.AddDays(-n)

$list1 = Import-CSV "c:ArchiveFileList1.csv

The columns used from the collection are:
MOVENUM – integer with the number of days or months

I then want to apply AddDays(-n) to find the date in the paste.
(Files older than that will be deleted separate from this piece of code).

switch ($list1)
DAYS {(Get-Date).AddDays(-$_.MOVENUM); break}
MONTHS {(Get-Date).AddMonths(-$_.MOVENUM); break}
default {Write-Output "Days or Months not specified."}

If this method, once corrected, will work for this idea, I would also like to populate a pre-defined column in the collection with that date returned by Switch.

I know I have many issues currently.

Should the declaration have the collection, or the collection.column?
switch ($list1)
switch ($list1.MOVEUNIT)

How does  AddDays refer to the MOVENUM column for the corresponding row reading MOVEUNIT given row?