Create a class of hierarchy list from list using LINQ

Hi
i have the below data , employee column consider as parent and each employee have invoice as child and each invoice have invoicedetails as subchild. i have binded this data into a list of class. now i want create hierarchy list from this list using LINQ

parent--->child--->subchild
Employee--->Invoice--->InvoiceDetails

List Data:

Employee invoice InvoiceDetails jan feb Mar Apr
E1 I1 ID1 1 2 10 5
E1 I1 ID2 1 3 11 6
E1 I1 ID3 1 4 12 7
E1 I2 ID1 1 5 13 8
E1 I2 ID2 1 6 14 9
E1 I2 ID3 1 7 15 10
E2 I1 ID1 1 8 16 11
E2 I1 ID2 1 10 17 12

Output :

E1
--I1
------ID1 1 2 10 5
------ID2 1 3 11 6
------ID3 1 4 12 7
--I2
------ID1 1 5 13 8
------ID2 1 6 14 9
------ID3 1 7 15 10
E2
--I1
---------ID1 1 8 16 11
---------ID2 1 10 17 12

Thanks

I have found a similar question on SO. If you play with the given answer, am sure you should be able to get what you need:

http://stackoverflow.com/questions/13745556/get-hierarchy-from-flat-datatable-using-linq-extension-methods?rq=1

You should be able to substitute your properties/classes in the example, and get your hierarchical list.

void Main()

{

	   Employee E1 = new Employee() { Id = 1 };

	   Employee E2 = new Employee() { Id = 2 };

	   Employee E3 = new Employee() { Id = 3 };

	   Invoice I1 = new Invoice() { Id = 1 };

	   Invoice I2 = new Invoice() { Id = 2 };

	   List list = new List();

	   list.Add(new FlatData() { Employee = E1, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );

	   list.Add(new FlatData() { Employee = E1, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 2 } } );

	   list.Add(new FlatData() { Employee = E1, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 3 } } );

	   list.Add(new FlatData() { Employee = E1, Invoice = I2, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );

	   list.Add(new FlatData() { Employee = E1, Invoice = I2, InvoiceDetail = new InvoiceDetail() { Id = 2 } } );

	   list.Add(new FlatData() { Employee = E1, Invoice = I2, InvoiceDetail = new InvoiceDetail() { Id = 3 } } );

	   list.Add(new FlatData() { Employee = E2, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );

	   list.Add(new FlatData() { Employee = E2, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );

	   foreach (Employee employee in BuildHierarchy(list))

{

		      Console.WriteLine("E" + employee.Id);

		      foreach (Invoice invoice in employee.Invoices)

{

			         Console.WriteLine("-   I" + invoice.Id);

			         foreach (InvoiceDetail invoiceDetail in invoice.InvoiceDetails)

{

				            Console.WriteLine("-   -   ID" + invoiceDetail.Id);

}

}

}

}

IEnumerable BuildHierarchy(IEnumerable entries)

{

	   return entries.GroupBy(entry => entry.Employee)

		      .Select(grouping => new Employee

{

				         Id = grouping.Key.Id,

				         Invoices = grouping.GroupBy(entry => entry.Invoice)

					               .Select(grouping2 => new Invoice

{

							                  Id = grouping2.Key.Id,

							                  InvoiceDetails = grouping2.Select(entry => new InvoiceDetail { Id = entry.InvoiceDetail.Id })

						         } )

}

);

}

class FlatData

{

	   public Employee Employee;

	   public Invoice Invoice;

	   public InvoiceDetail InvoiceDetail;

}

// Define other methods and classes here

class Employee

{

	   public int Id { get; set; }

	   public IEnumerable Invoices { get; set; }

}

class Invoice

{

	   public int Id { get; set; }

	   public IEnumerable InvoiceDetails { get; set; }

}

class InvoiceDetail

{

	   public int Id { get; set; }

}

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

Guest User10y ago
I have found a similar question on SO. If you play with the given answer, am sure you should be able to get what you need:

http://stackoverflow.com/questions/13745556/get-hierarchy-from-flat-datatable-using-linq-extension-methods?rq=1

You should be able to substitute your properties/classes in the example, and get your hierarchical list.

void Main()
{
   Employee E1 = new Employee() { Id = 1 };
   Employee E2 = new Employee() { Id = 2 };
   Employee E3 = new Employee() { Id = 3 };
   Invoice I1 = new Invoice() { Id = 1 };
   Invoice I2 = new Invoice() { Id = 2 };

   List list = new List();
   list.Add(new FlatData() { Employee = E1, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );
   list.Add(new FlatData() { Employee = E1, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 2 } } );
   list.Add(new FlatData() { Employee = E1, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 3 } } );
   list.Add(new FlatData() { Employee = E1, Invoice = I2, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );
   list.Add(new FlatData() { Employee = E1, Invoice = I2, InvoiceDetail = new InvoiceDetail() { Id = 2 } } );
   list.Add(new FlatData() { Employee = E1, Invoice = I2, InvoiceDetail = new InvoiceDetail() { Id = 3 } } );
   list.Add(new FlatData() { Employee = E2, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );
   list.Add(new FlatData() { Employee = E2, Invoice = I1, InvoiceDetail = new InvoiceDetail() { Id = 1 } } );
   foreach (Employee employee in BuildHierarchy(list))
   {
      Console.WriteLine("E" + employee.Id);
      foreach (Invoice invoice in employee.Invoices)
      {
         Console.WriteLine("- I" + invoice.Id);
         foreach (InvoiceDetail invoiceDetail in invoice.InvoiceDetails)
         {
            Console.WriteLine("- - ID" + invoiceDetail.Id);
         }
      }
   }
}
IEnumerable BuildHierarchy(IEnumerable entries)
{
   return entries.GroupBy(entry => entry.Employee)
      .Select(grouping => new Employee
      {
         Id = grouping.Key.Id,
         Invoices = grouping.GroupBy(entry => entry.Invoice)
               .Select(grouping2 => new Invoice
               {
                  Id = grouping2.Key.Id,
                  InvoiceDetails = grouping2.Select(entry => new InvoiceDetail { Id = entry.InvoiceDetail.Id })
         } )
      }
   );
}
class FlatData
{
   public Employee Employee;
   public Invoice Invoice;
   public InvoiceDetail InvoiceDetail;
}
// Define other methods and classes here
class Employee
{
   public int Id { get; set; }
   public IEnumerable Invoices { get; set; }
}
class Invoice
{
   public int Id { get; set; }
   public IEnumerable InvoiceDetails { get; set; }
}
class InvoiceDetail
{
   public int Id { get; set; }
}