Auto-Start-Stop-VM-Azure

Workflow Stop-Start-AzureVM 
{ 
    Param 
    (    
        [Parameter(Mandatory=$true)][ValidateNotNullOrEmpty()] 
        [String] 
        $AzureSubscriptionId, 
        [Parameter(Mandatory=$true)][ValidateNotNullOrEmpty()] 
        [String] 
        $AzureVMList="All", 
        [Parameter(Mandatory=$true)][ValidateSet("Start","Stop")] 
        [String] 
        $Action 
    ) 
     
    $credential = Get-AutomationPSCredential -Name 'automationname' 
    Login-AzureRmAccount -Credential $credential 
    Select-AzureRmSubscription -SubscriptionId $AzureSubscriptionId 
 
    if($AzureVMList -ne "All") 
    { 
        $AzureVMs = $AzureVMList.Split(",") 
        [System.Collections.ArrayList]$AzureVMsToHandle = $AzureVMs 
    } 
    else 
    { 
        $AzureVMs = (Get-AzureRmVM).Name 
        [System.Collections.ArrayList]$AzureVMsToHandle = $AzureVMs 
 
    } 
 
    foreach($AzureVM in $AzureVMsToHandle) 
    { 
        if(!(Get-AzureRmVM | ? {$_.Name -eq $AzureVM})) 
        { 
            throw " AzureVM : [$AzureVM] - Does not exist! - Check your inputs " 
        } 
    } 
 
    if($Action -eq "Stop") 
    { 
        Write-Output "Stopping VMs"; 
        foreach -parallel ($AzureVM in $AzureVMsToHandle) 
        { 
            Get-AzureRmVM | ? {$_.Name -eq $AzureVM} | Stop-AzureRmVM -Force 
        } 
    } 
    else 
    { 
        Write-Output "Starting VMs"; 
        foreach -parallel ($AzureVM in $AzureVMsToHandle) 
        { 
            Get-AzureRmVM | ? {$_.Name -eq $AzureVM} | Start-AzureRmVM 
        } 
    } 
}