使用 PowerShell 查詢電腦安裝的 .NET Framework 版本

function Get-DotNetVersionFromRegistry {
    $ndpKeyPath = "HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\"
    $ndpKey = Get-ItemProperty -Path $ndpKeyPath -ErrorAction SilentlyContinue

    if ($null -eq $ndpKey) {
        return "No 4.5 or later version detected"
    }

    # Hashtable mapping release keys to .NET Framework versions
    $versionMap = @{
        533320 = "4.8.1 or later";
        528040 = "4.8 or later";
        461808 = "4.7.2 or later";
        461308 = "4.7.1 or later";
        460798 = "4.7 or later";
        394802 = "4.6.2 or later";
        394254 = "4.6.1 or later";
        393295 = "4.6 or later";
        393273 = "4.6 RC or later";
        379893 = "4.5.2 or later";
        378675 = "4.5.1 or later";
        378389 = "4.5 or later";
    }

    $releaseKey = [int]$ndpKey.Release
    foreach ($key in $versionMap.Keys | Sort-Object -Descending) {
        if ($releaseKey -ge $key) {
            return $versionMap[$key]
        }
    }

    return "No 4.5 or later version detected"
}

# Main script execution
$version = Get-DotNetVersionFromRegistry
Write-Host ".NET Framework Version: $version"