Powershell - starting and stopping multiple app pools

The following powershell script defines some functions in Powershell that can start up or stop all iis app pools on a server. It can be handy when you want to test out concurrency issues and switch off all IIS app pools and start up again.

Function fnStartApplicationPool([string]$appPoolName){
Import-Module WebAdministration 
 if ((Get-WebAppPoolState $appPoolName).Value -ne 'Started') {
  Write-Host 'IIS app pool ' $appPoolName ' is not started. Starting.' 
  Start-WebAppPool -Name $appPoolName 
  Write-Host 'IIS app pool ' $appPoolName 'started' 
 }
}

Function fnStartAllApplicationPools() {
Import-Module WebAdministration  
 Write-Host "Starting all app pools" 
 $appPools = (Get-ChildItem IIS:\AppPools)

foreach ($appPool in $appPools) { 
  & fnStartApplicationPool -appPoolName $appPool.Name
}
}

#fnStartAllApplicationPools #start all applications pools


Function fnStopApplicationPool([string]$poolname) {
Import-Module WebAdministration 
 if ((Get-WebAppPoolState $appPoolName).Value -ne 'Stopped') {
  Stop-WebAppPool -Name $appPoolName 
 }
}

Function fnStopAllApplicationPools(){
Import-Module WebAdministration  
 Write-Host "Starting all app pools" 
 $appPools = (Get-ChildItem IIS:\AppPools)

foreach ($appPool in $appPools) { 
  & fnStopApplicationPool-appPoolName $appPool.Name
}  

}

#fnStopAllApplicationPools #start all applications pools