Windows PowerShell Sorting and grouping pipe results _powershell

Pipe results can be grouped by using Sort-object and Group-object.
In fact, the results of the execution of each command has been sorted out. For example, to view a list of files through LS, the default is to sort by the Name property, but you can sort by specifying attributes such as:

PS c:powershell> ls | Sort-object length
Mode     lastwritetime length Name
----     ------------------------a
---2011/11/   15:30   ping.bat-a
---2011/12/2   18:47 140 Test.ps1-a
---2011/11/28   16:42  170 Test.vbs-a
---2011/11/28   11:12  186 logotestconfig.xml-a
---2011/11/23   17:37  242 test.txt-a
---2011/11/25   11:20  556 employee.xml

This defaults to ascending sorting based on length, and if you want to arrange in descending order, use the descending option.

PS c:powershell> ls | Sort-object length-descending
Mode     lastwritetime Length Name
----     -----------------------
- A---2011/11/24   17:44 735892 powershell_cmdlets.html-a---2011/11/24 18:30 67580 a.html-a
---2011/ 11/24   20:04 26384 a.txt-a
---2011/11/29 19:23 21466 function.ps1-a
---2011/11/24   20:26 12060 alias-a
---2011/11/24   17:37  7420 name.html

To sort objects and hash tables

If you want to complete the primary keyword descending order, the sort of secondary keyword ascending, the first thing you might think of is:

PS c:powershell> Dir | Sort-object Length, name-descending,-ascending
sort-object: No positional arguments were found to accept the actual parameter "system.object[".
Location: 1 characters:
+ Dir | Sort-object <<<< Length, name-descending,-ascending
  + categoryinfo     : invalidargument: (:) [Sort-object], Parameterbin
  dingexception
  + fullyqualifiederrorid:positionalparameternotfound, Microsoft.PowerShell
  . Commands.sortobjectcommand

But the above method does not work, but this operation:

PS c:powershell> Dir | Sort-object @{expression= "Length";D escending= $true},@{ex
pression= "Name"; ascending= $true}

  directory: C:powershell

Mode     lastwritetime Length Name
----     -----------------------
-a---2011/11/24   17:44 735892 powershell_cmdlets.html
-a---2011/11/24
18:30 67580 a.html- A---2011/11/24 20:04 26384 a.txt-a---2011/11/29 19:23 21466 function.ps1-a
---2011/11/24   20:26 12060 alias-a
---2011/11/24 17:37 7420 name.html-a
---2011/12/14  11:22 3460 ls.html-a
---2011/11/30   16:04  2556 psdrive.html-a
---2011/11/25   11:20  556 Employee.xml-a
---2011/11/23   17:37  242 test.txt-a
---2011/11/28   11:12  186 Logotestconfig.xml-a
---2011/11/28   16:42  170 test.vbs-a
---2011/12/2   18:47  140 Test.ps1

grouping data

If you want to view all services that are currently closed and turned on, and group by state. But use:

PS c:powershell> Get-service | Group-object Status
Count Name  Group
---------  -----
  Running { System.ServiceProcess.ServiceController, SYSTEM.SERVICEPROCESS.S
       Ervicecontroller, System.ServiceProcess.ServiceController, System
       . Serviceprocess.servicecontroller ...}
  Stopped {System.ServiceProcess.ServiceController, system.serviceprocess.s
       Ervicecontroller, System.ServiceProcess.ServiceController, System
       . Serviceprocess.servicecontroller ...}

For example, the current directory files are grouped by extension .

PS c:powershell> ls | Group-object Extension
Count Name Group
--------------
  2    {ABC, alias}
  5. html {a.html, Ls.html, name.html, powershell_cmdlets.html ...}
  2. txt {a.txt, test.txt}
  2. xml {employee.xml, logotestconfig.xml}
  2. ps1 {function.ps1, test.ps1}
  1 bat {Ping.bat}
  1. vbs {TEST.VBS}

Grouping by using an expression

If you want to view the files for the current directory, group the file size by more than 1KB.

PS c:powershell> ls | Group-object {$_. Length-gt 1kb}

Count Name           Group
---------           -----
  7 False           {ABC, employee.xml, Logotestconfig.xml, ping ...
  8 True           {a.html, a.txt, alias, Function.ps1 ...}

If you grouped by the first letter of the file name

PS c:powershell> ls | Group-object {$_.name. SubString (0,1). ToUpper ()}
Count Name Group
--------------
  3 A  {a.html, a.txt, alias}
  1 E  {employee.xml}
  1 F  {FUNCTION.PS1}
  2 L  {logotestconfig.xml, ls.html}
  1 N  { name.html}
  3 P  {ping.bat, powershell_cmdlets.html, psdrive.html}
  3 T  {test.ps1, test.txt, Test.vbs}

Group by publisher of the current application

PS c:powershell> get-process | Group-object company-noelement

Count Name
---------
  2 Adobe Systems incorpor ...
  2 Microsoft
  Corporation
  1 Adobe Systems, Inc.
  1 Microsoft (R) Corporation
  1
  1 NVIDIA Corporation

grouping with formatting commands

Group-object is not the only command that can complete the grouping function, in fact, formatting commands such as Format-object support a groupby parameter, or they can complete the grouping.

PS c:powershell> Dir | Sort-object Extension, Name | Format-table-groupby Extension

  directory: C:powershell

Mode        lastwritetime   Length Name
----        ----- --------   ----------
-a---    2011/11/24   20:26   12060 alias

  directory: C:powershell

Mode        LastWriteTime   Length Name
----        -------------   -----------a
---    2011/11/28   15:30     ping.bat

  Table of Contents: C:powershell

Mode        lastwritetime   Length Name
----        -------------   -----------a
---    2011/11/   18:30   67580 a.html-a
---    2011/12/14 11:22 3460-a
---    ls.html   17:37    7420 name.html-a
---    2011/11/24   17:44   735892 powershell_cmdlets.html -A
---    2011/11/30   16:04    2556 psdrive.html