When you enter a command in PowerShell, the engine triggers three events to actually discover the command you want to execute. This gives you a number of opportunities to intercept and change command discovery. Let’s teach PowerShell to send command output to Out-GridView whenever you add “>>” to a command name!

Here is the code:

$ExecutionContext.InvokeCommand.PreCommandLookupAction = {
param
(
    [string]
    $Command,

    [Management.Automation.CommandLookupEventArgs]
    $Obj
)

    # when the command ends with ">>"...
    if ($Command.EndsWith('>>'))
    {
        # ...remove the ">>" from the command...
        $RealCommand = $Command.Substring(0, $Command.Length-2)
        # ...run the original command with its original arguments,
        # and pipe the results to a grid view window
        $obj.CommandScriptBlock = {
            & $RealCommand @args | Out-GridView
            # use a new "closure" to make the $RealCommand variable available
            # inside the script block when it is later called
        }.GetNewClosure()
    }
}

Next, enter these two commands:

 
PS C:\> Get-Process -Id $PID
PS C:\> Get-Process>> -Id $PID 
 

The first command simply dumps the current process. The second command sends the results to Out-GridView automatically.

If you want to get rid of the behavior again, restart PowerShell (or assign an empty script block to the event). If you want to make the behavior permanent, add the code above to your $profile script.


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