PowerShell: Detect Windows Version

This little snippet is reusable on many occasions where Windows version targeting is required.

function detectWindowsVersion{
    # Display Windows Version Name
    # $versionDigits=[Environment]::OSVersion.Version
    # (Get-WmiObject -class Win32_OperatingSystem).Caption
    # (Get-WmiObject -class Win32_OperatingSystem).Caption
    $windowsOS=Get-WmiObject -class Win32_OperatingSystem
    $windowsName=$windowsOS.Caption
    $windowsServicePack=$windowsOS.ServicePackMajorVersion
    $releaseID=(Get-ItemProperty "REGISTRY::HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion").ReleaseID;

    switch -wildcard ($windowsName){
    "Microsoft Windows XP*"{
        "Windows XP is way out of date. Turn it off asap."
        }
    "Microsoft Windows 7*"{
        "$windowsName has been detected...";
        if ($windowsServicePack -eq 1){
            # Windows 7 Service Pack 1 / Windows Server 2008 R2 Service Pack 1
            $GLOBAL:source = "http://download.windowsupdate.com/d/msdownload/update/software/secu/2018/05/windows6.1-kb4103718-x64_c051268978faef39e21863a95ea2452ecbc0936d.msu"
            $GLOBAL:kb="KB4103718"
            }else{
            "Windows 7 is no longer being supported by Michael Shop..."
            }
        break;     
        }
    "Microsoft Windows Server 2008*"{
        "$windowsName has been detected...";
            if ($windowsName -like "Microsoft Windows Server 2008 R2*"){
	        # Windows 7 Service Pack 1 / Windows Server 2008 R2 Service Pack 1
	        $GLOBAL:source = "http://download.windowsupdate.com/d/msdownload/update/software/secu/2018/05/windows6.1-kb4103718-x64_c051268978faef39e21863a95ea2452ecbc0936d.msu"
            $GLOBAL:kb="KB4103718"
            }else{
            "Windows 2008 is no longer being supported by Michael Shop..."
            }
        break;            
        }
    "Microsoft Windows Server 2012*"{         
        if ($windowsName -like "Microsoft Windows Server 2012 R2*"){
            "Microsoft Windows Server 2012 R2 has been detected...";
            # Windows 8.1 / Windows Server 2012 R2
	        $GLOBAL:source = "http://download.windowsupdate.com/d/msdownload/update/software/secu/2018/05/windows8.1-kb4103725-x64_cdf9b5a3be2fd4fc69bc23a617402e69004737d9.msu"	
            $GLOBAL:kb="KB4103725"
            }else{
                "Microsoft Windows Server 2012 has been detected...";
               # Windows Server 2012 Default
	           $GLOBAL:source = "http://download.windowsupdate.com/d/msdownload/update/software/secu/2018/04/windows8-rt-kb4103730-x64_1f4ed396b8c411df9df1e6755da273525632e210.msu"
               $GLOBAL:kb="KB4103730"
               }
        break;
        }
    "Microsoft Windows Server 2016*"{    
        "$windowsName release ID $releaseID has been detected...";
        switch ($releaseID){
                1607{
                # RS1 - Windows 10 version 1607 / Windows Server 2016	    	
	            $GLOBAL:source = "http://download.windowsupdate.com/d/msdownload/update/software/secu/2018/05/windows10.0-kb4103723-x64_2adf2ea2d09b3052d241c40ba55e89741121e07e.msu"
                $GLOBAL:kb="kb4103723"
                }
                1709{
                # RS3 - Windows 10 version 1709 / Windows Server 2016 version 1709
	            $GLOBAL:source = "http://download.windowsupdate.com/c/msdownload/update/software/secu/2018/05/windows10.0-kb4103727-x64_c217e7d5e2efdf9ff8446871e509e96fdbb8cb99.msu"
                $GLOBAL:kb="KB4103727"
                }
                1803{   
                # RS4 - Windows 10 1803 / Windows Server 2016 version 1803
	            $GLOBAL:source = "http://download.windowsupdate.com/c/msdownload/update/software/secu/2018/05/windows10.0-kb4103721-x64_fcc746cd817e212ad32a5606b3db5a3333e030f8.msu"
                $GLOBAL:kb="KB4103721"
                }	
            }
        break;
        }
    "Microsoft Windows 10*"{	
        "$windowsName release ID $releaseID has been detected...";
        switch ($releaseID){
                1607{	    	
	            # RS1 - Windows 10 version 1607
	            $GLOBAL:source = "http://download.windowsupdate.com/d/msdownload/update/software/secu/2018/05/windows10.0-kb4103723-x64_2adf2ea2d09b3052d241c40ba55e89741121e07e.msu"
                $GLOBAL:kb="KB4103723"
                }
                1703{    
                # RS2 - Windows 10 version 1703
	            $GLOBAL:source = "http://download.windowsupdate.com/c/msdownload/update/software/secu/2018/05/windows10.0-kb4103731-x64_209b6a1aa4080f1da0773d8515ff63b8eca55159.msu"
                $GLOBAL:kb="KB4103731"	            
                }
                1709{
                # RS3 - Windows 10 version 1709 / Windows Server 2016 version 1709
	            $GLOBAL:source = "http://download.windowsupdate.com/c/msdownload/update/software/secu/2018/05/windows10.0-kb4103727-x64_c217e7d5e2efdf9ff8446871e509e96fdbb8cb99.msu"
                $GLOBAL:kb="KB4103727"
                }
                1803{   
                # RS4 - Windows 10 1803 / Windows Server 2016 version 1803
	            $GLOBAL:source = "http://download.windowsupdate.com/c/msdownload/update/software/secu/2018/05/windows10.0-kb4103721-x64_fcc746cd817e212ad32a5606b3db5a3333e030f8.msu"
                $GLOBAL:kb="KB4103721"
                }
            }
            break;	
        }      
    }
}

detectWindowsVersion;