Windows Powershell ForEach-Object 迴圈_PowerShell

對管道對象逐個處理

如果使用Get-WmiObject 擷取系統中的服務，為了排版可能會也會使用Format-Table對結果進行表格排版。

複製代碼 代碼如下:

PS C:Powershell> Get-WmiObject Win32_Service | Format-Table status,DisplayName
-AutoSize

status DisplayName
------ -----------
OK     Adobe Acrobat Update Service
OK     Application Experience
OK     Application Layer Gateway Service
OK     Application Host Helper Service
OK     Application Identity
OK     Application Information
OK     Application Management
OK     ASP.NET State Service

但是如果想對每個服務進行更定製化的處理可是使用ForEach-Object

複製代碼 代碼如下:

PS C:Powershell> Get-WmiObject Win32_Service | ForEach-Object {"Name:"+ $_.Disp
layName, ", Is ProcessId more than 100:" + ($_.ProcessId -gt 100)}
Name:Adobe Acrobat Update Service , Is ProcessId more than 100:True
Name:Application Experience , Is ProcessId more than 100:False
Name:Application Layer Gateway Service , Is ProcessId more than 100:False
Name:Application Host Helper Service , Is ProcessId more than 100:True
Name:Application Identity , Is ProcessId more than 100:True
Name:Application Information , Is ProcessId more than 100:True
Name:Application Management , Is ProcessId more than 100:False
Name:ASP.NET State Service , Is ProcessId more than 100:False

結合條件處理

ForEach-Object的處理可以包含任意Powershell指令碼，當然也包括條件陳述式

複製代碼 代碼如下:

Get-WmiObject Win32_Service | ForEach-Object {
    if ($_.ProcessId -gt 3000)
    { "{0}({1})" -f $_.DisplayName,$_.ProcessID}
}
Windows Presentation Foundation Font Cache 3.0.0.0(5408)
Microsoft Network Inspection(5260)
BranchCache(4112)
Windows Modules Installer(7656)

調用方法

在ForEach-Object中，$_代表當前對象，當然也允許通過$_,調用該對象支援的方法。
下面的例子殺死所有IE瀏覽器進程：

複製代碼 代碼如下:

PS C:Powershell> Get-Process iexplore

Handles  NPM(K)    PM(K)      WS(K) VM(M)   CPU(s)     Id ProcessName
-------  ------    -----      ----- -----   ------     -- -----------
    883      29    14728      22432   181    34.26   4300 iexplore
    771      28    55552     129152   425     8.56   5732 iexplore
   1216      51   104324     143916   539   572.41   5912 iexplore
    801      25    49200      25372   285     5.99   6252 iexplore
    691      25    57564      95796   333     8.08   6388 iexplore
   1256      38    85848     127012   379    20.37   7856 iexplore

PS C:Powershell> Get-Process iexplore | ForEach-Object {$_.kill()}
PS C:Powershell> Get-Process iexplore
Get-Process : 找不到名為“iexplore”的進程。請驗證該進程名稱，然後再次調用 cmdlet。
所在位置 行:1 字元: 12
+ Get-Process <<<< iexplore
+ CategoryInfo : ObjectNotFound: (iexplore:String) [Get-Process],
ProcessCommandException
+ FullyQualifiedErrorId : NoProcessFoundForGivenName,Microsoft.PowerShell.
Commands.GetProcessCommand