Template.ps1

function Log
{
	param (
        $Object,
        $ForegroundColor,
        $BackgroundColor,
        [switch] $NoNewLine
    )
    
	Write-Host @PSBoundParameters

	$pathLog = "$([Environment]::GetFolderPath("Desktop"))\Log\$($timestamp).log"
	if (test-path $pathLog) {} else {mkdir $pathLog}

	$s = "$(Get-Date -format "[yyyy/MM/dd HH:mm:ss]")`t$Object"
	Add-Content "$pathLog\$(gc env:computername)_$(Get-Date -format "yyyyMMdd").log" -value $s
}

try
{
	Log "start!"
	#==========initialization==========
	$variables = "var"
	#==================================

	Log "initializing..."

	Log "processing $variables..."

	Log "done!"

    throw Exception
}
catch [Exception]
{
	$template = "{0} : {1}`r`n{2}`r`n" +
					"    + CategoryInfo          : {3}`r`n" +
					"    + FullyQualifiedErrorId : {4}`r`n"
	$values = $_.InvocationInfo.MyCommand.Name,
				$_.Exception.Message,
				$_.InvocationInfo.PositionMessage,
				$_.CategoryInfo.ToString(),
				$_.FullyQualifiedErrorId
    
	Log ($template -f $values)
}