Resolve-Host.Ps1

Function Resolve-Host()
{
    Param(
    [Parameter(Mandatory=$true,Position=0)] $HostEntry,
    [Switch] $HostnameToIP,
    [Switch] $FlushDNS
    )
    
    If($FlushDNS)
    {
        Ipconfig /FlushDNS | Out-Null
    }
   
    If($HostnameToIP)
    {
        $object = @()
        $HostEntry | %{
        
        
        $Object += New-Object psobject -Property @{  HostName= $_
                                                     IPAddress=$([System.Net.Dns]::gethostentry($_).AddressList.IPAddressToString)
                                                  }
                      }
        
        Return $object | select Hostname, IPAddress
    }
    else
    {
        $object = @()
        $HostEntry | %{
        
        
        $Object += New-Object psobject -Property @{  IPAddress= $_
                                                     HostName=$([System.Net.Dns]::gethostentry($_).HostName)
                                                  }
                      }
        
        Return $object | select IPAddress, Hostname
    }
}

#Must First run
. .\Resolve-Host.Ps1
there is space after the first dot

#Then
Resolve-Host "1.1.1.1","8.8.8.8"
Resolve-Host "bing.com" -HostnameToIP
Resolve-Host (gc .\IPAddresses.txt) | FT -AutoSize
Resolve-Host (gc .\IPAddresses.txt) -HostnameToIP | FT -AutoSize