Powershell: Create Event with parameters

This function will let you stamp events to the Windows EventLog, and feed the event with filterable parameterdata (which in the cases you use SCOM to sniff events, is pretty awesome).

I use this all the time in cases where a script should dump some kind of result to the eventlog, and using SCOM to fetch the event and trigger on special texts or values in the parameterdata returned.

function createParamEvent ()
  Function for creating events, just like create-event or eventcreate.exe - but with the added functionality to add up to 5 filterable parameters.
  The function stamps Windows Events to the Windows Eventlog by your choice, but can also be fed up to 5 different parameters, where param1 contains the basic Event Description, and param2 to param5 contains data of your choosing.
  For Information events, use eventID 220:
  CreateParamEvent -source "TestSource" -evtID 220 -param1 "The server $hostname shut down at $timestamp" -param2 $hostname -param3 $timestamp -param4 "Some generic text"
  For Warning events:
  CreateParamEvent -source "TestSource" -evtID 221 -param1 "The server $hostname shut down at $timestamp" -param2 $hostname -param3 $timestamp -param4 "some generic text"
  For Error events, with the manditory param1 set. All parameters from param2 to param5 are not manditory:
  CreateParamEvent -source "TestSource" -evtID 222 -param1 "The server $hostname shut down at $timestamp"
  Alle andre eventID'er vil logges som information events.
  Mandatory: The logic in this function is based on the principle where the sample eventIDs (222, 221, 220) will throw an error corresponding to the Event Type (error, warning, information). Other EventIDs can be used, but will then be logged as an Information Event.
  .PARAMETER param1
  Mandatory: The full description in the event.
  .PARAMETER param2-5
  Use theese parameters to add additional useful information to the mix, for example additional information that can be pulled from the Event in SCOM.
  - Param1 = Full description in the event
  - Source is mandetory
  - EventID is mandetory
  - Eventid 222 = Error event
  - Eventid 221 = Warning event
  - Eventid 220 = Information event
  - Param2 to 5 are optional.
    #Define the event log
    $evtlog = "Application"

    #Load the event source to the log if not already loaded.  This will fail if the event source is already assigned to a different log.
    if ([System.Diagnostics.EventLog]::SourceExists($source) -eq $false) {
        [System.Diagnostics.EventLog]::CreateEventSource($source, $evtlog)

    if ($evtID -eq 222){
    $id = New-Object System.Diagnostics.EventInstance($evtID,1,1); #ERROR EVENT
    elseif ($evtID -eq 221){
    $id = New-Object System.Diagnostics.EventInstance($evtID,1,2); #WARNING EVENT
    $id = New-Object System.Diagnostics.EventInstance($evtID,1); #INFORMATION EVENT
    $evtObject = New-Object System.Diagnostics.EventLog;
    $evtObject.Log = $evtlog;
    $evtObject.Source = $source;
    $evtObject.WriteEvent($id, @($param1,$param2,$param3,$param4,$param5))