Add-Type @'
public class CPObject
{
    public int id;
    public string name;
    public string displayname;
    public string classname;
    public string ip;
    public string netmask;
    public string ManagementServer;
}
'@

Function NameToIP {

    Param([int]$id=0, [string]$name="")

    $CPObject = $CPNetworkObjects | Where-Object { $_.id -eq $id -and $_.name -eq $name }

    If($CPObject.count -eq 1){
        $CPObject.ip
    } else {
        ""
    }
}

$NameToIP = @{}

Foreach ($Object in $Array) { $NameToIP["$($Object.id)_$($Object.Name)"] = $Object.ip }

Function NameToIP {

    Param([int]$id=0, [string]$name="")

    $NameToIP["$id_$name"]

 }

PS>(1..15000) |%{
>>> $res+=new-object pscustomobject -property @{"id"=$_;name=(get-random)}
>>> }

PS> measure-command -expression {$res |?{$_.id -eq 14999 -and $_.name -eq 513658722}}