test.cs

public class Invoice
{
	public string InvoiceID { get; set; }
	public Customer Customer { get; set; }
	public string InvoiceNumber { get; set; }
	public string InvoiceDate { get; set; }

	public List<LineItem> LineItems { get; set; }
}

public class LineItem
{
	public string LineItemID { get; set; }
	public string Description { get; set; }
	public string Quantity { get; set; }
	public string Price { get; set; }
	public string Tax { get; set; }
	public string Total { get; set; }
}

public class Customer
{
	public string CustomerID { get; set; }
	public string Name { get; set; }
	public string Email { get; set; }
	public string Phone { get; set; }

	public string Address { get; set; }
	public string City { get; set; }
	public string State { get; set; }

	public string Zip { get; set; }
	public string Country { get; set; }
}