class Program
{
static void Main(string[] args)
{
var employeeProducts = new List<EmployeeProduct>();
employeeProducts.Add(new EmployeeProduct(1, 2, "XYZ"));
employeeProducts.Add(new EmployeeProduct(1, 5, "ZXY"));
employeeProducts.Add(new EmployeeProduct(2, 2, "XYZ"));
var way1 = employeeProducts.Select(
ep => new ProductCount
{
ProductNumber = ep.ProductID,
EmployeeNumber = ep.EmployeeID,
CountProducts = employeeProducts.Count(epc => epc.ProductID == ep.ProductID)
});
var way2 = employeeProducts
.GroupBy(ep => ep.ProductID)
.SelectMany(epg => epg.Select(
ep => new ProductCount
{
ProductNumber = ep.ProductID,
EmployeeNumber = ep.EmployeeID,
CountProducts = epg.Count()
}));
}
public class EmployeeProduct
{
public EmployeeProduct(int employeeID, int productID, string name)
{
EmployeeID = employeeID;
ProductID = productID;
Name = name;
}
public int EmployeeID { get; set; }
public int ProductID { get; set; }
public string Name { get; set; }
}
public class ProductCount
{
public int ProductNumber { get; set; }
public int EmployeeNumber { get; set; }
public int CountProducts { get; set; }
}
}
