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Filtering dates using PowerShell

I realize this should be a simple task, but I am not seeing the results that I expect to see. I am importing a CSV file and trying to filter out the dates that have already passed and only keep the dates that are equal to today or in the future.

As a simple example, I have a csv file with the following:

enter image description here

If I run the following code, I am not seeing the expected results; dates that are equal today or in the future:

 $Today = Get-date

$data = import-csv C:\temp\ReleaseRequest2.csv
$data | where {$_.expires -ge $Today} | select expires

When I run the above, I receive the following results:

enter image description here

The goal is to only return dates that are equal to today or in the future. Is there formatting of the dates that I need to do before trying to filter them? I know it is a simple solution, but I am banging my head against a wall trying to figure it out.

Thank in advance.

Solution

  • Convert the dates into a datetime object before you compare them, you can see why your code is failing with this simple test:

    $today = Get-Date
'11/26/2024 8:55' -ge $today            # true
[datetime] '11/26/2024 8:55' -ge $today # false

    So, in your filtering condition if you add the cast to [datetime] the issue should be solved:

    $today = Get-Date
$data = Import-Csv C:\temp\ReleaseRequest2.csv
$data | Where-Object { [datetime] $_.Expires -ge $Today }

    Using Get-Date to parse them should also work:

    $data | Where-Object { (Get-Date $_.Expires) -ge $Today }

    If those options above fail to convert the strings into datetime objects, you can use datetime.ParseExact with the format strings your dates have, for example:

    [datetime]::ParseExact(
    '1/28/2025 8:55', 'M/d/yyyy H:mm', [cultureinfo]::InvariantCulture)