在Powershell中使用Group-Object和-GroupBy

使用Group-Object(group)按组统计

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | group Noun

 Count Name              Group
 ----- ----              -----
     3 LocalGroupMember  {Add-LocalGroupMember, Get-LocalGroupMember, Remove-LocalGroupMember}
     7 LocalUser         {Disable-LocalUser, Enable-LocalUser, Get-LocalUser, New-LocalUser, Remove-LocalUser, Rename-LocalUser, Set-LocalUser}
     5 LocalGroup        {Get-LocalGroup, New-LocalGroup, Remove-LocalGroup, Rename-LocalGroup, Set-LocalGroup}   

对统计的结果进行排序，注意：以下两个语句是等效的

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | sort Noun | group Noun

 Count Name              Group
 ----- ----              -----
     5 LocalGroup        {Get-LocalGroup, New-LocalGroup, Remove-LocalGroup, Rename-LocalGroup, Set-LocalGroup}
     3 LocalGroupMember  {Add-LocalGroupMember, Get-LocalGroupMember, Remove-LocalGroupMember}
     7 LocalUser         {Disable-LocalUser, Enable-LocalUser, Get-LocalUser, New-LocalUser, Remove-LocalUser, Rename-LocalUser, Set-LocalUser}    

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | group Noun | sort Name

 Count Name              Group
 ----- ----              -----
     5 LocalGroup        {Get-LocalGroup, New-LocalGroup, Remove-LocalGroup, Rename-LocalGroup, Set-LocalGroup}
     3 LocalGroupMember  {Add-LocalGroupMember, Get-LocalGroupMember, Remove-LocalGroupMember}
     7 LocalUser         {Disable-LocalUser, Enable-LocalUser, Get-LocalUser, New-LocalUser, Remove-LocalUser, Rename-LocalUser, Set-LocalUser} 

在Format-Table里使用-GroupBy按组显示结果，必须先对Groupby的字段进行排序，否则Groupby的字段不会显示在一起

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | sort Noun | ft -GroupBy Noun
 

    Noun: LocalGroup

 CommandType     Name                                               Version    Source
 -----------     ----                                               -------    ------
 Cmdlet          Get-LocalGroup                                     1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          New-LocalGroup                                     1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Remove-LocalGroup                                  1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Rename-LocalGroup                                  1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Set-LocalGroup                                     1.0.0.0    Microsoft.PowerShell.LocalAccounts                                          

    Noun: LocalGroupMember

 CommandType     Name                                               Version    Source
 -----------     ----                                               -------    ------
 Cmdlet          Add-LocalGroupMember                               1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Get-LocalGroupMember                               1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Remove-LocalGroupMember                            1.0.0.0    Microsoft.PowerShell.LocalAccounts                                          

    Noun: LocalUser

 CommandType     Name                                               Version    Source
 -----------     ----                                               -------    ------
 Cmdlet          Disable-LocalUser                                  1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Enable-LocalUser                                   1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Get-LocalUser                                      1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          New-LocalUser                                      1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Remove-LocalUser                                   1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Rename-LocalUser                                   1.0.0.0    Microsoft.PowerShell.LocalAccounts
 Cmdlet          Set-LocalUser                                      1.0.0.0    Microsoft.PowerShell.LocalAccounts   

Format-Table处理以后，一般不能再进行"|"操作，否则会出错

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | ft -AutoSize

 CommandType Name                    Version Source
 ----------- ----                    ------- ------
 Cmdlet      Add-LocalGroupMember    1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Disable-LocalUser       1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Enable-LocalUser        1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Get-LocalGroup          1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Get-LocalGroupMember    1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Get-LocalUser           1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      New-LocalGroup          1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      New-LocalUser           1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Remove-LocalGroup       1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Remove-LocalGroupMember 1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Remove-LocalUser        1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Rename-LocalGroup       1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Rename-LocalUser        1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Set-LocalGroup          1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Set-LocalUser           1.0.0.0 Microsoft.PowerShell.LocalAccounts

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | ft -AutoSize | sort Name

 out-lineoutput : The object of type "Microsoft.PowerShell.Commands.Internal.Format.FormatEntryData" is not valid or not in the
 correct sequence. This is likely caused by a user-specified "format-*" command which is conflicting with the default formatting
 .
     + CategoryInfo          : InvalidData: (:) [out-lineoutput], InvalidOperationException
     + FullyQualifiedErrorId : ConsoleLineOutputOutOfSequencePacket,Microsoft.PowerShell.Commands.OutLineOutputCommand

有时候虽然能执行，但结果也和预期不符

 PS C:\> Get-Command -Module Microsoft.PowerShell.LocalAccounts | ft -AutoSize | group Noun

 Count Name                      Group
 ----- ----                      -----
    19                           {Microsoft.PowerShell.Commands.Internal.Format.FormatStartData, Microsoft.PowerShell.Command...

 PS C:\> $data = Get-Command -Module Microsoft.PowerShell.LocalAccounts | ft -AutoSize | group Noun

 PS C:\> $data.Group

 CommandType Name                    Version Source
 ----------- ----                    ------- ------
 Cmdlet      Add-LocalGroupMember    1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Disable-LocalUser       1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Enable-LocalUser        1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Get-LocalGroup          1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Get-LocalGroupMember    1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Get-LocalUser           1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      New-LocalGroup          1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      New-LocalUser           1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Remove-LocalGroup       1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Remove-LocalGroupMember 1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Remove-LocalUser        1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Rename-LocalGroup       1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Rename-LocalUser        1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Set-LocalGroup          1.0.0.0 Microsoft.PowerShell.LocalAccounts
 Cmdlet      Set-LocalUser           1.0.0.0 Microsoft.PowerShell.LocalAccounts

最后，Group-Object(group)这个cmdlet在Microsoft.PowerShell.Utility这个Module里，不在Microsoft.PowerShell.Core里

 PS C:\> Get-Command *-Object* | sort Source | ft -AutoSize

 CommandType Name                 Version Source
 ----------- ----                 ------- ------
 Cmdlet      ForEach-Object       3.0.0.0 Microsoft.PowerShell.Core
 Cmdlet      Where-Object         3.0.0.0 Microsoft.PowerShell.Core
 Cmdlet      Compare-Object       3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      Group-Object         3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      Measure-Object       3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      New-Object           3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      Register-ObjectEvent 3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      Select-Object        3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      Sort-Object          3.1.0.0 Microsoft.PowerShell.Utility
 Cmdlet      Tee-Object           3.1.0.0 Microsoft.PowerShell.Utility

 PS C:\> Alias | where DisplayName -like "*Object*" | select Definition, Name | sort Definition

 Definition       Name
 ----------       ----
 Compare-Object   compare
 Compare-Object   diff
 ForEach-Object   %
 ForEach-Object   foreach
 Get-WmiObject    gwmi
 Group-Object     group
 Measure-Object   measure
 Remove-WMIObject rwmi
 Select-Object    select
 Sort-Object      sort
 Tee-Object       tee
 Where-Object     ?
 Where-Object     where