Wait-Event

SYNOPSIS

Waits until a particular event is raised before continuing to run.

SYNTAX

Wait-Event [[-SourceIdentifier] <String>] [-Timeout <Int32>] [<CommonParameters>]

DESCRIPTION

The `Wait-Event` cmdlet suspends execution of a script or function until a particular event is raised. Execution resumes when the event is detected. To cancel the wait, press \<kbd>CTRL\</kbd>+\<kbd>C\</kbd>.

This feature provides an alternative to polling for an event. It also allows you to determine the response to an event in two different ways:

using the Action parameter of the event subscription - waiting for an event to return and then respond with an action

EXAMPLES

Example 1: Wait for the next event

Wait-Event

Example 2: Wait for an event with a specified source identifier

Wait-Event -SourceIdentifier "ProcessStarted"

Example 3: Wait for a timer elapsed event

$Timer = New-Object Timers.Timer
$objectEventArgs = @{
    InputObject = $Timer
    EventName = 'Elapsed'
    SourceIdentifier = 'Timer.Elapsed'
}
Register-ObjectEvent @objectEventArgs
$Timer.Interval = 2000
$Timer.Autoreset = $False
$Timer.Enabled = $True
Wait-Event Timer.Elapsed

ComputerName     :
RunspaceId       : bb560b14-ff43-48d4-b801-5adc31bbc6fb
EventIdentifier  : 1
Sender           : System.Timers.Timer
SourceEventArgs  : System.Timers.ElapsedEventArgs
SourceArgs       : {System.Timers.Timer, System.Timers.ElapsedEventArgs}
SourceIdentifier : Timer.Elapsed
TimeGenerated    : 4/23/2020 2:30:37 PM
MessageData      :

Example 4: Wait for an event after a specified timeout

Wait-Event -SourceIdentifier "ProcessStarted" -Timeout 90

PARAMETERS

-SourceIdentifier

Specifies the source identifier that this cmdlet waits for events. By default, `Wait-Event` waits for any event.

Type: System.String
Parameter Sets: (All)
Aliases:

Required: False
Position: 0
Default value: None
Accept pipeline input: True (ByPropertyName)
Accept wildcard characters: False

-Timeout

Specifies the maximum time, in seconds, that `Wait-Event` waits for the event to occur. The default, -1, waits indefinitely. The timing starts when you submit the `Wait-Event` command.

If the specified time is exceeded, the wait ends and the command prompt returns, even if the event has not been raised. No error message is displayed.

Type: System.Int32
Parameter Sets: (All)
Aliases: TimeoutSec

Required: False
Position: Named
Default value: -1
Accept pipeline input: False
Accept wildcard characters: False

CommonParameters

This cmdlet supports the common parameters: -Debug, -ErrorAction, -ErrorVariable, -InformationAction, -InformationVariable, -OutVariable, -OutBuffer, -PipelineVariable, -Verbose, -WarningAction, and -WarningVariable. For more information, see about_CommonParameters.

INPUTS

System.String

OUTPUTS

System.Management.Automation.PSEventArgs

NOTES

Events, event subscriptions, and the event queue exist only in the current session. If you close the current session, the event queue is discarded and the event subscription is canceled.