Compare Date from CSV Import To Get-Date - date

Question

I have a CSV that contains a number of columns but I want to import just the description column, a department column and a date column. I then want to create a new object with the description, department and date information but only for items that have a date 45 days or older. I know that the Import-Csv is bringing in the "Item Date" column as a string so that I need to use something like Get-Date or datetime to get it to a date format for comparison.
$data = import-csv .\items.csv | select "Description", "Department", "Item Date"
$CheckDate = (Get-Date).AddDays(-45)
$data2 | Foreach {get-date $_."Item Date"} |
select "Description", "Department", "Item Date"
$newdata = $data2 | where {$data."Item Date" -lt $CheckDate}
There may be an easier way to do this or there may be a way to get this to work but I am having trouble.

Answer 1

Definitely some room for simplification here.
$CheckDate = (Get-Date).AddDays(-45)
$data = Import-Csv .\items.csv |
Where-Object {
($_."Item Date" -as [DateTime]) -lt $CheckDate
}
Just cast the "Item Date" string as a [DateTime] with the -as operator and then compare that to your $CheckDate in the Where-Object call.

Answer 2

Depending on the date format used in the CSV and the computer's regional settings simply casting the string to a DateTime value may or may not work. If you find that it doesn't use the ParseExact() method instead. And perhaps a calculated property, since you're selecting columns anyway.
$fmt = 'dd\/mm\/yyyy'
$culture = [Globalization.CultureInfo]::InvariantCulture
$data = Import-Csv .\items.csv |
Select-Object Description, Department, #{n='Item Date';e={
[DateTime]::ParseExact($_.'Item Date', $fmt, $culture)
}} |
Where-Object { $_.'Item Date' -lt $CheckDate }
Note that forward slashes in the format string must be escaped if you need to match literal forward slashes, otherwise they will match whatever date separator character is configured in the computer's regional settings.