gci 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' |
sort pschildname -des                                  |
select -fi 1 -exp pschildname

如果安装了，这个答案不会返回4.5。下面的答案来自@Jaykul和使用递归。

我不熟悉PowerShell语法，但我认为您可以调用System.Runtime.InteropServices.RuntimeEnvironment.GetSystemVersion()。这将以字符串的形式返回版本(我认为类似于v2.0.50727)。

如果你要使用注册表，你必须递归才能得到完整版本的4。x框架。前面的答案都返回了。net 3.0系统上的根数(其中WCF和WPF的数字，嵌套在3.0下，更高——我无法解释)，而4.0则没有返回任何东西……

编辑:对于。net 4.5及以上版本，这又发生了轻微的变化，所以现在有一篇很好的MSDN文章解释了如何将发布值转换为。net版本号，这完全是一场灾难:-(

这对我来说是正确的(注意它在3.0上为WCF和WPF输出单独的版本号。我不知道那是怎么回事)。它还输出客户端和完整的4.0(如果你有他们都安装):

Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release

根据MSDN文章，您可以构建一个查找表，并返回4.5之后发行版的营销产品版本号:

$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'
    528040 = [version]'4.8'
    528049 = [version]'4.8'
}

# For One True framework (latest .NET 4x), change the Where-Object match 
# to PSChildName -eq "Full":
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -Recurse |
  Get-ItemProperty -name Version, Release -EA 0 |
  Where-Object { $_.PSChildName -match '^(?!S)\p{L}'} |
  Select-Object @{name = ".NET Framework"; expression = {$_.PSChildName}}, 
@{name = "Product"; expression = {$Lookup[$_.Release]}}, 
Version, Release

事实上，由于我必须不断更新这个答案，这里有一个脚本，从该网页的markdown源代码生成上面的脚本(带有一点额外的内容)。这可能会在某个时候崩溃，所以我保持上面的当前副本。

# Get the text from github
$url = "https://raw.githubusercontent.com/dotnet/docs/master/docs/framework/migration-guide/how-to-determine-which-versions-are-installed.md"
$md = Invoke-WebRequest $url -UseBasicParsing
$OFS = "`n"
# Replace the weird text in the tables, and the padding
# Then trim the | off the front and end of lines
$map = $md -split "`n" -replace " installed [^|]+" -replace "\s+\|" -replace "\|$" |
    # Then we can build the table by looking for unique lines that start with ".NET Framework"
    Select-String "^.NET" | Select-Object -Unique |
    # And flip it so it's key = value
    # And convert ".NET FRAMEWORK 4.5.2" to  [version]4.5.2
    ForEach-Object { 
        [version]$v, [int]$k = $_ -replace "\.NET Framework " -split "\|"
        "    $k = [version]'$v'"
    }

# And output the whole script
@"
`$Lookup = @{
$map
}

# For extra effect we could get the Windows 10 OS version and build release id:
try {
    `$WinRelease, `$WinVer = Get-ItemPropertyValue "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion" ReleaseId, CurrentMajorVersionNumber, CurrentMinorVersionNumber, CurrentBuildNumber, UBR
    `$WindowsVersion = "`$(`$WinVer -join '.') (`$WinRelease)"
} catch {
    `$WindowsVersion = [System.Environment]::OSVersion.Version
}

Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -Recurse |
    Get-ItemProperty -name Version, Release -EA 0 |
    # For The 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,
    # Some OPTIONAL extra output: PSComputerName and WindowsVersion
    # The Computer name, so output from local machines will match remote machines:
    @{ name = "PSComputerName"; expression = {`$Env:Computername}},
    # The Windows Version (works on Windows 10, at least):
    @{ name = "WindowsVersion"; expression = { `$WindowsVersion }}
"@

我想在PowerShell中试试这个: 为我工作!

(Get-ItemProperty "HKLM:Software\Microsoft\NET Framework Setup\NDP\v4\Full")。版本

[environment]::Version

为当前PSH副本正在使用的CLR提供一个Version实例(如本文所述)。

以下是我对这个问题的看法:

$gpParams = @{
    Path        = 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full'
    ErrorAction = 'SilentlyContinue'
}
$release = Get-ItemProperty @gpParams | Select-Object -ExpandProperty Release

".NET Framework$(
    switch ($release) {
        ({ $_ -ge 528040 }) { ' 4.8'; break }
        ({ $_ -ge 461808 }) { ' 4.7.2'; break }
        ({ $_ -ge 461308 }) { ' 4.7.1'; break }
        ({ $_ -ge 460798 }) { ' 4.7'; break }
        ({ $_ -ge 394802 }) { ' 4.6.2'; break }
        ({ $_ -ge 394254 }) { ' 4.6.1'; break }
        ({ $_ -ge 393295 }) { ' 4.6'; break }
        ({ $_ -ge 379893 }) { ' 4.5.2'; break }
        ({ $_ -ge 378675 }) { ' 4.5.1'; break }
        ({ $_ -ge 378389 }) { ' 4.5'; break }
        default { ': 4.5+ not installed.' }
    }
)"

这个例子适用于所有PowerShell版本，并且将永远工作，因为4.8是最后一个。net Framework版本。