PowerShell, stream Process output and errors while running external process

Is there any way in PowerShell I can stream the content of the Output and the Error while the process is running? In pure .NET we can subscribe to events of the Process class, can I do the same in PowerShell?

Sure you can! What you need is an Object Events:

An object event is a .Net object that not only has the usual Properties and Methods in the object, but also has another member called Event, which you can register a subscription on using Register-ObjectEvent

Here is slightly modified example from the the PowerShell forums. It will output data from the ping command asynchronously (at least from the script point of view):

# Setup stdin\stdout redirection$StartInfo = New-Object System.Diagnostics.ProcessStartInfo -Property @{                FileName = 'ping.exe'                Arguments = '-t 127.0.0.1'                UseShellExecute = $false                RedirectStandardOutput = $true                RedirectStandardError = $true            }# Create new process$Process = New-Object System.Diagnostics.Process# Assign previously created StartInfo properties$Process.StartInfo = $StartInfo# Register Object Events for stdin\stdout reading$OutEvent = Register-ObjectEvent -Action {    Write-Host $Event.SourceEventArgs.Data} -InputObject $Process -EventName OutputDataReceived$ErrEvent = Register-ObjectEvent -Action {    Write-Host $Event.SourceEventArgs.Data} -InputObject $Process -EventName ErrorDataReceived# Start process[void]$Process.Start()# Begin reading stdin\stdout$Process.BeginOutputReadLine()$Process.BeginErrorReadLine()# Do something else while events are firingdo{    Write-Host 'Still alive!' -ForegroundColor Green    Start-Sleep -Seconds 1}while (!$Process.HasExited)# Unregister events$OutEvent.Name, $ErrEvent.Name |    ForEach-Object {Unregister-Event -SourceIdentifier $_}