在 Register-ObjectEvent 的操作中执行函数的 Powershell 控制台问题

Question

在 powershell ISE 中工作正常，但在控制台中我得到:

The term 'MainAction' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

如何修复？

function MainAction () {
    $test = "123"
    Write-Host $test
}

MainAction

$action = {
    try {
        Write-Host in action
        MainAction
    } catch {
        Write-Host $Error    
        $timer.Stop()
        Unregister-Event thetimer
    }
}

$timer = New-Object Timers.Timer    
Register-ObjectEvent -InputObject $timer -EventName elapsed `
                     -SourceIdentifier thetimer -Action $action -OutVariable out
$timer.Interval = 5000
$timer.AutoReset = $true
$timer.Start()

编辑:

我发现我可以使用配置文件来存储函数定义。至create profile使用:

New-Item -path $profile -itemType file -force

但我仍然很感兴趣，为什么 powershell ISE 不需要配置文件来存储和使用 Register-ObjectEvent 操作中的函数。

Answer 1

当您使用 Register-ObjectEvent 注册 -Action 时，PowerShell 将创建新的动态模块来承载该操作。因此，作为结果，只有全局范围在事件处理程序和其余代码之间共享。因此，您应该将所有需要的函数放在全局范围内:

function global:MainAction {
    Write-Host 'Do something'
}

$Action = { MainAction }

$Timer = New-Object Timers.Timer
$EventJob = Register-ObjectEvent -InputObject $Timer -EventName Elapsed -Action $Action

$Timer.Interval = 5000
$Timer.AutoReset = $true
$Timer.Start()

或者将它们显式添加到由 PowerShell 创建的动态模块的范围内:

$Action = { MainAction }

$Timer = New-Object Timers.Timer
$EventJob = Register-ObjectEvent -InputObject $Timer -EventName Elapsed -Action $Action

. $EventJob.Module {
    function MainAction {
        Write-Host 'Do something'
    }
}

$Timer.Interval = 5000
$Timer.AutoReset = $true
$Timer.Start()