Updated on Kisan Patel
You can use the into keyword to store the results of a select, group, or join statement in a temporary variable.
You might use this construction when you need to execute additional queries over the results. Because of this behavior, this keyword is also called a continuation clause.
For Example,
var query = from p in persons
where p.Name.StartsWith("K")
select p
into pNames
where pNames.Name.Length > 4
select pNames;
Common use of into is with grouping.
using System;
using System.Collections.Generic;
using System.Linq;
namespace ConsoleApp
{
class Program
{
static void Main(string[] args)
{
List persons = new List{
new Person{ Name = "Kisan", City="Ladol" },
new Person{ Name = "Kite", City = "Ladol" },
new Person{ Name = "Ketul", City = "Vijapur" },
new Person{ Name = "Kisan", City = "Vijapur" },
};
var query = from p in persons
where p.Name.StartsWith("K")
select p
into pNames
where pNames.Name.Length > 4
select pNames;
foreach (var name in query)
Console.WriteLine(name.Name + " - " + name.City);
}
}
public class Person
{
public string Name { get; set; }
public string City { get; set; }
}
}
the output of the above C# program…
Here is another example of how to use “into” keyword with join?
using System;
using System.Collections.Generic;
using System.Linq;
namespace ConsoleApp
{
class Program
{
static void Main(string[] args)
{
List customers = new List{
new Customer{ Id = 1, Name = "Kisan", City="Ladol" },
new Customer{ Id = 2, Name = "Kite", City = "Ladol" },
new Customer{ Id = 3, Name = "Ketul", City = "Vijapur" },
new Customer{ Id = 4, Name = "Kisan", City = "Vijapur" },
};
List orders = new List{
new Order{ OrderId = 1, CustomerId = 2},
new Order{ OrderId = 2, CustomerId = 3},
new Order{ OrderId = 3, CustomerId = 2},
new Order{ OrderId = 4, CustomerId = 1},
};
var query = from c in customers
join o in orders on c.Id equals o.CustomerId
into Purchases
from p in Purchases
select new { c.Id, c.Name, p.CustomerId };
foreach (var name in query)
Console.WriteLine(name.CustomerId + " - " + name.Name);
}
}
public class Customer
{
public int Id { get; set; }
public string Name { get; set; }
public string City { get; set; }
}
public class Order
{
public int OrderId { get; set; }
public int CustomerId { get; set; }
}
}
the output of the above C# program…
