哈希 table 是前进的方向吗?

Is a hash table the way forward?

我有一个看起来像这样的变量:

Plugin ID     : 66334
Host          : GCAB-L7-449090L
Plugin Output : . Microsoft Operating System Patches :
                + To patch the remote system, you need to install the following Microsoft patches :
                - KB3167679 (MS16-101) (2 vulnerabilities)The following CVEs would be covered: 
                CVE-2016-3300, CVE-2016-3237
                - KB3114340 (MS16-099) (133 vulnerabilities)The following CVEs would be covered: 
                CVE-2016-3313, CVE-2016-3315, CVE-2016-3316, CVE-2016-3317, CVE-2016-3318, 
                - KB3115427 (MS16-099) (133 vulnerabilities)The following CVEs would be covered: 
                CVE-2016-3313, CVE-2016-3315, CVE-2016-3316, CVE-2016-3317, CVE-2016-3318

Plugin ID     : 66334
Host          : GCAB-L7-449096R
Plugin Output : . Microsoft Operating System Patches :
                + To patch the remote system, you need to install the following Microsoft patches :
                - KB3167679 (MS16-101) (2 vulnerabilities)The following CVEs would be covered: 
                CVE-2016-3300, CVE-2016-3237
                - KB3177725 (MS16-099) (58 vulnerabilities)The following CVEs would be covered: 
                CVE-2016-3313, CVE-2016-3315, CVE-2016-3316, CVE-2016-3317, CVE-2016-3318

我想要完成的是一个包含主机的 KB 数组。我认为哈希表是可行的方法,但如果是的话,我就缺少对它们的理解的关键部分。这是我的代码:

$filtered = $data | Where-Object {[string]$_."Plugin ID" -eq "66334"}

foreach ($item in $filtered)
{
    $machine = $item.Host
    $kbs = Select-String -InputObject $item.'Plugin Output' -Pattern $regex -AllMatches |
           ForEach-Object { $_.Matches }

    foreach ($k in $kbs)
    {
        if ($hash.ContainsKey($k))
        {
            #The KB is already a part of the hash table.  Edit the key value to include the new host.
        }
        else
        {
            $hash[$k] = $machine
        }
    }
}

如果密钥不存在,则将其添加到散列中,否则我将修改现有密钥的值以包含新主机。不幸的是,我的 if 语句继续只执行 else 子句。

我想得到的是:

KB                 Host

KB3167679           GCAB-L7-449090L, GCAB-L7-449096R
KB3114340           GCAB-L7-449090L
KB3115427           GCAB-L7-449090L
KB3177725           GCAB-L7-449096R

所以,有几个问题:

  1. 为什么 $hash.ContainsKey() 不在这里为我工作?
  2. 哈希表是我想要的方式吗?

是的,哈希表是可行的方法。 $hash.ContainsKey() 对您不起作用,因为您将 $kbs 设为 MatchInfo 对象的列表,而不是将匹配值扩展为字符串。

正如其他人已经建议的那样,您可以将另一个 ForEach-Object 添加到您的管道中

$kbs = Select-String -InputObject $item.'Plugin Output' -Pattern $regex -AllMatches |
       ForEach-Object { $_.Matches } | ForEach-Object { $_.Value }

或(如果您有 PowerShell v3 或更新版本)使用 member enumeration

$kbs = Select-String -InputObject $item.'Plugin Output' -Pattern $regex -AllMatches |
       ForEach-Object { $_.Matches.Value }

获取实际的字符串值。