調用cmdlet時使用變量作爲動詞

Question

我正在嘗試編寫一個腳本來啓動，停止或重新啓動遠程計算機上的服務。

我發現這一點：

Start-Service -InputObject $(Get-Service -Computer COMPUTER1 -Name spooler) 

，並開始在周圍建造我的腳本。

這是我有：

$Action = Read-Host "Start, Stop or Restart service?" 
$Serv = Read-Host "Service name?" 
$Comp = Read-Host "Computer name?" 
"$Action"-Service -InputObject $(Get-Service -Computer "$Comp" -Name "$Serv") 

當我運行此腳本，我得到這個錯誤：

At U:\Serv.ps1:4 char:10 
+ "$Action"-Service -InputObject $(Get-Service -Computer "$Comp" -Name "$Serv") 
+   ~~~~~~~~ 
Unexpected token '-Service' in expression or statement. 
At U:\Serv.ps1:4 char:19 
+ "$Action"-Service -InputObject $(Get-Service -Computer "$Comp" -Name "$Serv") 
+     ~~~~~~~~~~~~ 

我已經試過這個：

$Action = Read-Host "Start, Stop or Restart service?" 
$Action = $Action + "-Service" 
$Serv = Read-Host "Service name?" 
$Comp = Read-Host "Computer name?" 
"$Action" -InputObject $(Get-Service -Computer "$Comp" -Name "$Serv") 

，但我得到類似的錯誤：

At U:\Serv.ps1:5 char:11 
+ "$Action" -InputObject $(Get-Service -Computer "$Comp" -Name "$Serv") 
+   ~~~~~~~~~~~~ 
Unexpected token '-InputObject' in expression or statement. 
At U:\Serv.ps1:5 char:24 
+ "$Action" -InputObject $(Get-Service -Computer "$Comp" -Name "$Serv") 
+      ~~ 
Unexpected token '$(' in expression or statement. 
    + CategoryInfo   : ParserError: (:) [], ParseException 
    + FullyQualifiedErrorId : UnexpectedToken 

    Unexpected token '-InputObject' in expression or statement. 
     + CategoryInfo   : ParserError: (:) [], ParseException 
     + FullyQualifiedErrorId : UnexpectedToken 

如何將輸入 - 「開始」，「停止」或「重新啓動」傳遞給命令的動詞部分？

Answer 1

這是使用PowerShell管理服務的一種相當複雜的方式。考慮做這樣的代替：

$Action = Read-Host "Start, Stop or Restart service?" 
$Serv = Read-Host "Service name?" 
$Comp = Read-Host "Computer name?" 

$svc = Get-Service -Computer $Comp -Name $Serv 
switch ($Action) { 
    'Start' { $svc | Start-Service } 
    'Stop' { $svc | Stop-Service } 
    'Restart' { $svc | Restart-Service } 
} 

如果由於某種原因，你必須構建cmdlet名稱必須使用電話運營商（&）：

& $Action ... 

如果沒有運營商的PowerShell將無法識別您的字符串作爲cmdlet，但會（嘗試）通過Out-Default進行打印。

而且，考慮使用，而不是Read-Host主機UI的PromptForChoice()方法：

$message = 'Manage Services' 
$question = 'Start, Stop or Restart service?' 

$choices = New-Object Collections.ObjectModel.Collection[Management.Automation.Host.ChoiceDescription] 
$choices.Add((New-Object Management.Automation.Host.ChoiceDescription -ArgumentList '&Start')) 
$choices.Add((New-Object Management.Automation.Host.ChoiceDescription -ArgumentList 'Sto&p')) 
$choices.Add((New-Object Management.Automation.Host.ChoiceDescription -ArgumentList '&Restart')) 

$Action = $Host.UI.PromptForChoice($message, $question, $choices, 0) 

switch ($Action) { 
    0 { $svc | Start-Service } 
    1 { $svc | Stop-Service } 
    2 { $svc | Restart-Service } 
} 

Answer 2

下面的代碼：

$message = 'Manage Services' 
$question = 'Start, Stop or Restart service?' 
$message 
Write-Host 
$Comp = Read-Host "Computer name?" 
Write-Host 
$ListServ = Read-Host "List services on remote computer? y or n" 
If ($ListServ -eq "y") 
    { 
    Get-Service -ComputerName $Comp 
    } 
Write-Host 
$Serv = Read-Host "Service name?" 
Write-Host 

$choices = New-Object Collections.ObjectModel.Collection[Management.Automation.Host.ChoiceDescription] 
$choices.Add((New-Object Management.Automation.Host.ChoiceDescription -ArgumentList '&Start')) 
$choices.Add((New-Object Management.Automation.Host.ChoiceDescription -ArgumentList 'Sto&p')) 
$choices.Add((New-Object Management.Automation.Host.ChoiceDescription -ArgumentList '&Restart')) 

$Action = $Host.UI.PromptForChoice($message, $question, $choices, 0) 
$svc = Get-Service -ComputerName $Comp -Name $Serv 
switch ($Action) { 
    0 { $svc | Start-Service } 
    1 { $svc | Stop-Service } 
    2 { $svc | Restart-Service } 
} 
$svc