How to record/audit changes for Insert/Add C# EF4

Question

Is there a non-complex way of auditing Entity Changes for insert/add? I use the code below to record Entity changes for Edit/Update

var context = new DBEntities(connection());
try
{
    BPCategory Bp = context.BPCategories.First(e => e.id == id);
    Bp.Category = Category;
    Bp.PercentShare = Percent;
    Bp.BPCategory1 = BPCategory;
    Bp.Code = Code;
    Bp.Status = Inactive;


    var objState = context.ObjectStateManager.GetObjectStateEntry(Bp);
    var modProps = objState.GetModifiedProperties();
    foreach (var propName in modProps)
    {
        if (!Equals(objState.OriginalValues[propName], objState.CurrentValues[propName]))
        {
            //save audit
        }
    }
    context.SaveChanges();
}
catch (Exception ex)
{
    throw ex;
}

But i'm struggling when it comes to add/insert. How can i do this for insert/add?

var context = new DBEntities(connection());
BPCategory Bp = new BPCategory
{
    Category = Category,
    PercentShare = PercentShare,
    BPCategory1 = BPCategory,
    Code = Code,
    Status = Inactive
};
context.BPCategories.AddObject(Bp);
context.SaveChanges();