Remove-TempFiles.ps1

#region Info

<#
	#################################################
	# modified by     : Joerg Hochwald
	# last modified   : 2016-05-28
	#################################################

	Support: https://github.com/jhochwald/NETX/issues
#>

#endregion Info

#region License

<#
	Copyright (c) 2012-2016, NET-Experts <http:/www.net-experts.net>.
	All rights reserved.

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	   this list of conditions and the following disclaimer.

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	   this list of conditions and the following disclaimer in the documentation
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	3. Neither the name of the copyright holder nor the names of its
	   contributors may be used to endorse or promote products derived from
	   this software without specific prior written permission.

	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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	ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
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	By using the Software, you agree to the License, Terms and Conditions above!
#>

#endregion License

function global:Remove-TempFiles {
<#
	.SYNOPSIS
		Removes all temp files older then a given time period

	.DESCRIPTION
		Removes all temp files older then a given time period from the system or the user environment.

	.PARAMETER Month
		Remove temp files older then X month.
		The default is 1

	.PARAMETER Context
		Remove the System or User Temp Files?
		The default is All.

	.EXAMPLE
		PS C:\> Remove-TempFiles -Confirm:$false

		TotalSize                     Retrieved                   TotalSizeMB                   RetrievedMB
		---------                     ---------                   -----------                   -----------
		518485778                     417617315                         494,5                         398,3

		Description
		-----------
		Removes all 'User' and 'System' temp file older then one month,
		without asking if you are sure! This could be dangerous...

	.EXAMPLE
		PS C:\> Remove-TempFiles -Confirm:$false
		WARNING: The process cannot access the file 'C:\Users\josh\AppData\Local\Temp\FXSAPIDebugLogFile.txt' because it is being used by another process. - Line Number: 96

		TotalSize                       Retrieved                     TotalSizeMB                     RetrievedMB
		---------                       ---------                     -----------                     -----------
		264147489                       214105710                           251,9                           204,2

		Description
		-----------
		Removes all 'User' and 'System' temp file older then one month,
		without asking if you are sure! This could be dangerous...

		One file is locked by another process! Just a warning will show up,
		the cleanup will continue.

	.EXAMPLE
		PS C:\> Remove-TempFiles -Month 3 -Context 'System'
		[Y] Yes  [A] Yes to All  [N] No  [L] No to All  [S] Suspend  [?] Help (default is "Y")

		TotalSize                       Retrieved                     TotalSizeMB                     RetrievedMB
		---------                       ---------                     -----------                     -----------
		264147489                       214105710                           251,9                           204,2

		Description
		-----------
		Removes all 'System' temp files older then 3 month

	.EXAMPLE
		PS C:\> Remove-TempFiles -Month 3 -Context 'User'
		[Y] Yes  [A] Yes to All  [N] No  [L] No to All  [S] Suspend  [?] Help (default is "Y")

		TotalSize                       Retrieved                     TotalSizeMB                     RetrievedMB
		---------                       ---------                     -----------                     -----------
		151519609                       145693231                           144,5                           138,9

		Description
		-----------
		Removes all 'User' temp files older then 3 month.

	.NOTES
		Adopted from a snippet found on Powershell.com

	.LINK
		Source http://powershell.com/cs/blogs/tips/archive/2016/05/27/cleaning-week-deleting-temp-files.aspx
#>

	[CmdletBinding(ConfirmImpact = 'High',
				   SupportsShouldProcess = $true)]
	[OutputType([System.Object])]
	param
	(
		[Parameter(Position = 1,
				   HelpMessage = 'Remove temp files older then X month.')]
		[System.Int64]$Month = 1,
		[Parameter(ValueFromPipeline = $true,
				   Position = 2,
				   HelpMessage = 'Remove the System or User Temp Files?')]
		[ValidateSet('System', 'User', 'All', IgnoreCase = $true)]
		[System.String]$Context = 'All'
	)

	#requires -Version 3
	#Requires -RunAsAdministrator

	BEGIN {
		# Look at temp files older than given period
		$cutoff = ((Get-Date).AddMonths(- $Month))

		# Use an ordered hash table to store logging info
		$sizes = [Ordered]@{ }
	}

	PROCESS {
		if ($Context -eq 'System') {
			$Target = "$env:windir\temp"
		} elseif ($Context -eq 'User') {
			$Target = "$env:temp"
		} elseif ($Context -eq 'All') {
			$Target = "$env:windir\temp", $env:temp
		} else {
			Write-Error -Message "I have no idea what to clean: $($Target)" -ErrorAction:Stop

			# Still here? Make sure we are done!
			break

			# Aw Snap! We are still here? Fix that the hard way...
			exit 1
		}

		if ($pscmdlet.ShouldProcess("$($Context)", "Remove Temp file older then $($Month)")) {
			<#
				Mind the Pipes. All in a very long command :-)
			#>
			# Find all files in both temp folders recursively
			Get-ChildItem $Target -Recurse -Force -File |
			# calculate total size before cleanup
			ForEach-Object {
				$sizes['TotalSize'] += $_.Length
				$_
			} |
			# take only outdated files
			Where-Object { $_.LastWriteTime -lt $cutoff } |
			# Try to delete. Add retrieved file size only if the file could be deleted
			ForEach-Object {
				try {
					$fileSize = $_.Length

					Remove-Item -Path $_.FullName -Force -Confirm:$false -ErrorAction Stop -WarningAction SilentlyContinue

					$sizes['Retrieved'] += $fileSize
				} catch [System.Exception] {
					Write-Warning "$($_.Exception.Message) - Line Number: $($_.InvocationInfo.ScriptLineNumber)"
				} catch {
					# Did not see this one coming!
					Write-Warning "Unable to remove $($_.FullName)"
				}
			}
		}
	}

	END {
		# Turn bytes into MB
		$Sizes['TotalSizeMB'] = [Math]::Round(($Sizes['TotalSize']/1MB), 1)
		$Sizes['RetrievedMB'] = [Math]::Round(($Sizes['Retrieved']/1MB), 1)

		# Dump the info
		New-Object -TypeName PSObject -Property $sizes
	}
}

Update: Better Examples!