Src/Private/Get-SystemUptime.ps1

function Get-SystemUptime {
    <#
    .SYNOPSIS
        Used by As Built Report to retrieve last boot uptime information
    .DESCRIPTION
 
    .NOTES
        Version: 0.1.1
        Author: AsBuiltReport Community
        Twitter: @AsBuiltReport
        Github: AsBuiltReport
    .EXAMPLE
 
    .LINK
 
    #>

    [CmdletBinding()]
    [OutputType([TimeSpan])]
    param (
    )

    begin {}

    process {
        $operatingSystem = Get-CimInstance -ClassName Win32_OperatingSystem | Select-Object LastBootUpTime
        $Uptime = "$((Get-Date) - ($operatingSystem.LastBootUpTime))"
        return [TimeSpan]$Uptime
    }

    end {}
}