Try like this
$dsNames = Get-Content .\luns.txt
Get-Datastore -Name $dsNames | %{
$obj = [ordered]@{
Datastore = $_.Name
VM = ''
}
$i = 1
(Get-View -Id $_.ExtensionData.VM -property Name).Name | %{
If($i -gt 1){
$obj.Datastore = ''
}
$obj.VM = $_
$i++
New-Object PSObject -Property $obj
}
} | Export-Csv D:\Temp\report.csv -NoTypeInformation -UseCulture
