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powershellazure-automation

Convert string to datetime in Azure automation Account (powershell)

I am trying to get the difference in days between a string datetime and the current date. I tried following code on my local PC

$Dateinname = "24-05-2022"
$Retention = (New-TimeSpan -Start $DateInName -End (get-date)).Days

        if ($Retention -gt 14){
           //do something
         }

However in Automation Account 'Powershell script', the same code provides following error:

New-TimeSpan : Cannot bind parameter 'Start'. Cannot convert value "[datetime]::parseexact" to type "System.DateTime". Error: "String was not recognized as a valid DateTime." At line:72 char:43 + ... $Retention = (New-TimeSpan -Start [datetime]::parseexact($DateIn ... + ~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidArgument: (:) [New-TimeSpan], ParameterBindingException + FullyQualifiedErrorId : CannotConvertArgumentNoMessage,Microsoft.PowerShell.Commands.NewTimeSpanCommand

I changed the start conversion multiple times with

  1. [datetime]DateInName
  2. [datetime]::parseexact($DateInName, 'dd-MMM-yyyy', $null)
  3. changed the '-' into '/'.

But still the automation account fails. Is there something I missed when creating the runbook like inscript, is there a model I forgot to install ?

Solution

  • As requested, here my comment as answer

    The date format in $DateInName shows it is formatted as 'dd-MM-yyyy'
    (2-digit Day, 2-digit Month, 4digit Year).

    Either do

    $DateInName = [datetime]::ParseExact('24-05-2022', 'dd-MM-yyyy', $null)
$Retention = (New-TimeSpan -Start $DateInName -End (get-date)).Days

    Or, if you want to perform this conversion inside the New-TimeSpan call, wrap it in brackets (..):

    $DateInName = '24-05-2022'
$Retention = (New-TimeSpan -Start ([datetime]::ParseExact($DateInName, 'dd-MM-yyyy', $null)) -End (Get-Date)).Days