Windows-classic-samples/Samples/PowerShell/EventRegistration

Windows PowerShell Event Registration Sample

This sample shows how to create a cmdlet for event registration by deriving from ObjectEventRegistrationBase.

The sample creates the Register-FileSystemEvent cmdlet which subscribes to events raised by System.IO.FileSystemWatcher. With this cmdlet, users can register an action to execute when a specific event is raised, such as when a file is created under an specific directory.

Sample Objectives

This sample demonstrates the following:

• How to how to derive from the ObjectEventRegistrationBase class to create a cmdlet for event registration.

Related topics

Windows PowerShell

System.IO.FileSystemWatcher

ObjectEventRegistrationBase

Operating system requirements

Client

Windows 8.1

Server

Windows Server 2012 R2

Build the sample

1. Start Microsoft Visual Studio and select File > Open > Project/Solution.

2. Go to the directory named for the sample, and double-click the Visual Studio Solution (.sln) file.

3. Press F7 or use Build > Build Solution to build the sample.

   The library will be built in the default \bin or \bin\Debug directory.

Run the sample

1. Start PowerShell and import the library file in order to make the Register-FileSystemEvent cmdlet available in PowerShell.
2. Use the Register-FileSystemEvent cmdlet to register an action that will write a message when a file is created under the TEMP directory.
3. Create a file under the TEMP directory and note that the action is executed (i.e. the message is displayed).

This is the sample output from executing these 3 steps:

cmd
PS> Import-Module .\bin\Debug\Events01.dll PS> Register-FileSystemEvent $env:temp Created -filter "*.txt" -action { Write-Host "A file was created in the TEMP directory" } Id Name State HasMoreData Location Command 1 26932870-d3b... NotStarted False Write-Host "A f... PS> Set-Content $env:temp\test.txt "This is a test file" A file was created in the TEMP directory PS>