Linq query expression

Question

I am writing a join query that produces an anonymous result set. My problem is that I don't know which data type should be returned from my function service and I tried to return object type but I don't know how to access the elements of result in my source code...

Here is my code:

 public static IEnumerable<object> GetProductSalesInfoById(int id)
 {
     var query = from product in database.Products
         join sales in database.SalesOrderDetails
             on product.ProductID equals sales.ProductID
         select new  {Name = product.Name,OrderId = sales.SalesOrderID,TotalPrice = (sales.UnitPriceDiscount)*sales.OrderQty*sales.UnitPrice};

     IEnumerable<object> result = query.ToList();
     return result;
 } 

Answer 1

crate one custom class like this

public partial class ResultClass
    {
     public string Name {get;set;}
     public int OrderId {get;set;}
     public double TotalPrice {get;set;}
    }

public List<ResultClass>  GetProductSalesInfoById(int id)
 {
     var query = from product in database.Products
         join sales in database.SalesOrderDetails
             on product.ProductID equals sales.ProductID
         select new ResultClass {Name = product.Name,OrderId = sales.SalesOrderID,TotalPrice = (sales.UnitPriceDiscount)*sales.OrderQty*sales.UnitPrice};


     return result.ToList();
 } 

hope this will help you out.

Answer 2

You can use Tuple or anonymous type(you need to use casting to get back the object). Check this link for usage : Anonymous & tuple objects

Answer 3

You should create a DTO class that contains the properties in your anonymous object and return an IEnumerable<T> of it. Another not so good solution is to use dynamic but I wouldn't use that.