Nice solution
Try using the downloadable DotNetVersionLister module (based on registry infos and some version-to-marketing-version lookup table).
Which would be used like this:
PS> Get-DotNetVersion -LocalHost -nosummary
ComputerName : localhost
>=4.x : 4.5.2
v4\Client : Installed
v4\Full : Installed
v3.5 : Installed
v3.0 : Installed
v2.0.50727 : Installed
v1.1.4322 : Not installed (no key)
Ping : True
Error :
Or like this if you just want to test it for some .NET framework >= 4.*:
PS> (Get-DotNetVersion -LocalHost -nosummary).">=4.x"
4.5.2
But it will not work (install/import) e.g. with PS v2.0 (Win 7, Win Server 2010 standard) due to incompatibility...
Motivation for "legacy" functions below
(You could skip reading this and use code below)
We had to work with PS 2.0 on some machines and could not install/import the above DotNetVersionLister.
On other machines we wanted to update (from PS 2.0) to PS 5.1 (which in turn needs .NET Framework >= 4.5) with the help of two company-custom Install-DotnetLatestCompany and Install-PSLatestCompany.
To guide admins nicely through the install/update process we would have to determine the .NET version in these functions on all machines and PS versions existing.
Thus we used also the below functions to determine them more safely in all environments...
Functions for legacy PS environments (e.g. PS v2.0)
So the following code and below (extracted) usage examples are useful here (based on other answers here):
function Get-DotNetVersionByFs {
<#
.SYNOPSIS
NOT RECOMMENDED - try using instead:
Get-DotNetVersion
from DotNetVersionLister module (https://github.com/EliteLoser/DotNetVersionLister),
but it is not usable/importable in PowerShell 2.0
Get-DotNetVersionByReg
reg(istry) based: (available herin as well) but it may return some wrong version or may not work reliably for versions > 4.5
(works in PSv2.0)
Get-DotNetVersionByFs (this):
f(ile) s(ystem) based: determines the latest installed .NET version based on $Env:windir\Microsoft.NET\Framework content
this is unreliable, e.g. if 4.0* is already installed some 4.5 update will overwrite content there without
renaming the folder
(works in PSv2.0)
.EXAMPLE
PS> Get-DotnetVersionByFs
4.0.30319
.EXAMPLE
PS> Get-DotnetVersionByFs -All
1.0.3705
1.1.4322
2.0.50727
3.0
3.5
4.0.30319
.NOTES
from https://stackoverflow.com/a/52078523/1915920
#>
[cmdletbinding()]
param(
[Switch]$All ## do not return only latest, but all installed
)
$list = ls $Env:windir\Microsoft.NET\Framework |
?{ $_.PSIsContainer -and $_.Name -match '^v\d.[\d\.]+' } |
%{ $_.Name.TrimStart('v') }
if ($All) { $list } else { $list | select -last 1 }
}
function Get-DotNetVersionByReg {
<#
.SYNOPSIS
NOT RECOMMENDED - try using instead:
Get-DotNetVersion
From DotNetVersionLister module (https://github.com/EliteLoser/DotNetVersionLister),
but it is not usable/importable in PowerShell 2.0.
Determines the latest installed .NET version based on registry infos under 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP'
.EXAMPLE
PS> Get-DotnetVersionByReg
4.5.51209
.EXAMPLE
PS> Get-DotnetVersionByReg -AllDetailed
PSChildName Version Release
----------- ------- -------
v2.0.50727 2.0.50727.5420
v3.0 3.0.30729.5420
Windows Communication Foundation 3.0.4506.5420
Windows Presentation Foundation 3.0.6920.5011
v3.5 3.5.30729.5420
Client 4.0.0.0
Client 4.5.51209 379893
Full 4.5.51209 379893
.NOTES
from https://stackoverflow.com/a/52078523/1915920
#>
[cmdletbinding()]
param(
[Switch]$AllDetailed ## do not return only latest, but all installed with more details
)
$Lookup = @{
378389 = [version]'4.5'
378675 = [version]'4.5.1'
378758 = [version]'4.5.1'
379893 = [version]'4.5.2'
393295 = [version]'4.6'
393297 = [version]'4.6'
394254 = [version]'4.6.1'
394271 = [version]'4.6.1'
394802 = [version]'4.6.2'
394806 = [version]'4.6.2'
460798 = [version]'4.7'
460805 = [version]'4.7'
461308 = [version]'4.7.1'
461310 = [version]'4.7.1'
461808 = [version]'4.7.2'
461814 = [version]'4.7.2'
}
$list = Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -Recurse |
Get-ItemProperty -name Version, Release -EA 0 |
# For One True framework (latest .NET 4x), change match to PSChildName -eq "Full":
Where-Object { $_.PSChildName -match '^(?!S)\p{L}'} |
Select-Object `
@{
name = ".NET Framework" ;
expression = {$_.PSChildName}},
@{ name = "Product" ;
expression = {$Lookup[$_.Release]}},
Version, Release
if ($AllDetailed) { $list | sort version } else { $list | sort version | select -last 1 | %{ $_.version } }
}
Example usage:
PS> Get-DotNetVersionByFs
4.0.30319
PS> Get-DotNetVersionByFs -All
1.0.3705
1.1.4322
2.0.50727
3.0
3.5
4.0.30319
PS> Get-DotNetVersionByReg
4.5.51209
PS> Get-DotNetVersionByReg -AllDetailed
.NET Framework Product Version Release
-------------- ------- ------- -------
v2.0.50727 2.0.50727.5420
v3.0 3.0.30729.5420
Windows Communication Foundation 3.0.4506.5420
Windows Presentation Foundation 3.0.6920.5011
v3.5 3.5.30729.5420
Client 4.0.0.0
Client 4.5.2 4.5.51209 379893
Full 4.5.2 4.5.51209 379893