Reacting to events

Events in .NET occur when something of interest happens to an object. For instance, System.IO.FileSystemWatcher can be used to monitor a filesystem for changes; when something changes, an event will be raised.

Many different types of objects raise events when changes occur. Get-Member can be used to explore an instance of an object for Event members. For example, a Process object returned by the Get-Process command includes a number of events, shown as follows:

PS> Get-Process | Get-Member -MemberType Event

    TypeName: System.Diagnostics.Process

Name                 MemberType    Definition
----                 ----------    ----------
Disposed             Event         System.EventHandler Disposed(System.Object, System.EventArgs)
ErrorDataReceived    Event         System.Diagnostics.DataReceivedEventHandler ErrorDataReceived(S...
Exited               Event ...