en-us/about_OnQ.help.txt
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### Getting Started with OnQ
OnQ is a PowerShell module that helps you use events to script asynchronously. It gives you an easy syntax to describe events handlers in PowerShell, and provides a platform to build custom event sources. You can watch for events to occur with Watch-Event. Watch-Event is aliased to "On". For example: ~~~PowerShell # Run in a second Watch-Event Delay "00:00:01" { "In A Second!" | Out-Host } # Or, using the alias 'On' on delay "00:05:00" { "Five more minutes!" | Out-Host} ~~~ These example use the built-in event source script 'Delay'. OnQ gives you a way to write scripts that will produce events. These are event sources. OnQ ships with several event sources. To see what event sources are available to you, run: ~~~PowerShell Get-EventSource # See event sources ~~~ Each event source discovered when OnQ loads creates a smart alias that makes it easier to discover parameters, for example: ~~~PowerShell # Run in 30 seconds On@Delay "00:00:30" { "This Message Will Self-Destruct in 30 seconds" | Out-Host } # Run at 5:00 PM On@Time "5:00 PM" { "End Of Day!" | Out-Host } # Run every 2 minutes On@Repeat "00:02:00" { "Every other minute" | Out-Host } # Run whenever a file changes within the current directory On@FileChange { "Files Changed:$($event.SenderEventArgs)" | Out-Host } ~~~ OnQ also allows you to handle an arbitrary signal. In the example below, we set up a handler for "MySignal", and the use the alias send to Send-Event(s). ~~~PowerShell On MySignal {"Fire $($event.MessageData)!" | Out-Host } # Send-Event can accept pipeline input for MessageData, and will not output unless -PassThru is specified. 1..3 | Send MySignal ~~~ --- [Understanding Event Sources](Understanding_Event_Sources.md) |