Here is an example of aggregation using LINQ to a collection -
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace GroupByExampleLinq
{
public class Person
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string Email { get; set; }
public string AccountNumber { get; set; }
}
class Program
{
static void Main(string[] args)
{
Example();
Console.ReadKey();
}
static void Example()
{
// Creating new List of Person
List personCollection = new List()
{
//Adding a new Person
new Person(){
AccountNumber = "123123 634566",
Email = "qwerty@qwerty.com",
FirstName = "John",
LastName = "Doe"
},
//Adding a new Person
new Person(){
AccountNumber = "123123 678879",
Email = "qwerty@qwerty.com",
FirstName = "John",
LastName = "Doe"
},
//Adding a new Person
new Person(){
AccountNumber = "123123 122134",
Email = "qwerty@qwerty.com",
FirstName = "John",
LastName = "Doe"
},
//Adding a new Person
new Person(){
AccountNumber = "123123 890980",
Email = "asdf@asdf.com",
FirstName = "Jane",
LastName = "Doe"
}
};
// Using LINQ to query the collection and group them by the email address
var personQuery = from p in personCollection
group p by p.Email into g
select new { Email = g.Key, Accounts = g };
// Output the email address and the count of records for each group
foreach (var item in personQuery)
{
Console.WriteLine("{0} has {1} accounts.", item.Email, item.Accounts.Count());
}
}
}
}
