compareorwhatdafok

public class allreadyAssigned
{
    public int id { get; set; }
    public string externalXref { get; set; }
}
public class ownerIdfinder
{
    public string id { get; set; }
    public string externalXref { get; set; }
}

JavaScriptSerializer js = new JavaScriptSerializer();
ids = js.Deserialize<ownerIdfinder[]>(streamReader.ReadToEnd());

JavaScriptSerializer allreadyjs = new JavaScriptSerializer();
allreadyIds = allreadyjs.Deserialize<allreadyAssigned[]>(allreadystreamReader.ReadToEnd());