Powershell - Get the first and last day of the month (Australia)

Get-FirstAndLastDays.ps1

$date = Get-Date 
$numMonthsAgo = -1


$firstDayOfMonth = Get-Date ((("01/" + (Get-Date $date).Month).ToString() + "/" + ((Get-Date $date).Year).ToString() + " 00:00:00"))
$lastDayOfMonth = (Get-Date ((("01/" + ((($firstDayOfMonth).AddMonths(1)).Month).ToString() + "/" + ((($firstDayOfMonth).AddMonths(1)).Year).ToString())))) - (New-TimeSpan -seconds 1)

$firstDayOfMonth = $firstDayOfMonth.AddMonths($numMonthsAgo)
$lastDayOfMonth = $lastDayOfMonth.AddMonths($numMonthsAgo)

Write-Host ("-StartDate " + (Get-Date $firstDayOfMonth -format d) + " -EndDate " + (Get-Date $lastDayOfMonth -format d))

# Find my folder that contains a file that I created n months ago
$items = Get-ChildItem "C:\users\skycoder" -Recurse | Where { $_.CreationTime -igt $firstDayOfMonth -and $_.CreationTime -ilt $lastDayOfMonth -and $_.PSIsContainer  } |
Select FullName, PSParentPath | Write-Host

You're better off making it date format agnostic. If you have a date in $date:

$startofmonth = Get-Date $date -day 1 -hour 0 -minute 0 -second 0
$endofmonth = (($startofmonth).AddMonths(1).AddSeconds(-1))

This will result in this (I had a date in Feb 2016 in there for testing):

PS C:\Temp> $startofmonth

Wednesday, 1 February 2016 12:00:00 AM

PS C:\temp> $endofmonth

Wednesday, 29 February 2016 11:59:59 PM

@MRQ - Thanks
Function parm defaults to current date. Function returns a date array with:
Date Supplied
First Day of Month
Last Day of Month

Function GetFirstLastDayOfMonth ( $aDate=$(get-date) ) {

$aDateSet=@($aDate)

$firstDay = Get-Date $aDate -day 1 -hour 0 -minute 0 -second 0
$lastDay = (($firstDay).AddMonths(1).AddSeconds(-1))

$aDateSet+=$firstDay
$aDateSet+=$lastDay

Return $aDateSet

}

Allows calls like below:
$x = GetFirstLastDayOfMonth # JULY 22, 2014
$y = GetFirstLastDayOfMonth $(get-date).AddMonths( -3 )
$x[1] # first day of current month
$x[2] # last day of current month
$x[0] # date supplied for computation

Tuesday, July 22, 2014 2:09:21 PM
Tuesday, July 01, 2014 12:00:00 AM
Thursday, July 31, 2014 11:59:59 PM

$y[0]
$y[1]
$y[2]

Tuesday, April 22, 2014 2:10:11 PM
Tuesday, April 01, 2014 12:00:00 AM
Wednesday, April 30, 2014 11:59:59 PM

Might need some error check if .typeOf is not a date on supplied parameter