powershell で .NET Framework のバージョンを確認

powershell のバージョン

PS C:\> $PSVersionTable

Name                           Value
----                           -----
PSVersion                      4.0
WSManStackVersion              3.0
SerializationVersion           1.1.0.1
CLRVersion                     4.0.30319.34209
BuildVersion                   6.3.9600.17400
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0}
PSRemotingProtocolVersion      2.2

.NET Framework 4 系のみですが以下のレジストリから情報を取得できます。

PS C:\> get-item 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full'


    Hive: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4


Name                           Property
----                           --------
Full                           Version       : 4.5.51650
                               CBS           : 1
                               TargetVersion : 4.0.0
                               Install       : 1
                               InstallPath   : C:\Windows\Microsoft.NET\Framework64\v4.0.30319\
                               Servicing     : 0
                               Release       : 379893

Release 番号からバージョンを参照します。
Release 番号についてはこちら

switch 文にすると簡単かなと。

$release = (get-item 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full').GetValue("Release")

switch -Exact ($release)
{
    "378389" { Write-Host ".NET Framework 4.5" }
    "378675" { Write-Host ".NET Framework 4.5.1 on Windows 8.1" }
    "378758" { Write-Host ".NET Framework 4.5.1 on Windows vista/7/8" }
    "379893" { Write-Host ".NET Framework 4.5.2" }
    "393295" { Write-Host ".NET Framework 4.6 on Windows 10" }
    "393297" { Write-Host ".NET Framework 4.6" }
    "394254" { Write-Host ".NET Framework 4.6.1 on Windows 10" }
    "394271" { Write-Host ".NET Framework 4.6.1" }
    "394802" { Write-Host ".NET Framework 4.6.2 on Windows 10" }
    "394806" { Write-Host ".NET Framework 4.6.2" }
    "460798" { Write-Host ".NET Framework 4.7 on Windows 10" }
    "460805" { Write-Host ".NET Framework 4.7" }
    "461308" { Write-Host ".NET Framework 4.7.1 on Windows 10" }
    "461310" { Write-Host ".NET Framework 4.7.1" }
    "461808" { Write-Host ".NET Framework 4.7.2 on Windows 10" }
    "461814" { Write-Host ".NET Framework 4.7.2" }
    "528040" { Write-Host ".NET Framework 4.8 on Windows 10" }
    "528049" { Write-Host ".NET Framework 4.8" } 
    default { Write-Host "Unknown version" }
}