Grouping data with a LINQ query
I have a C# DataTable with 5 columns in it. I only care about two of the columns in the DataTable. The two columns I c开发者_开发问答are about are called "CreateDate" and "ID". They are a DateTime and string. The DateTime represents the date on which a ticket was submitted. The ID uniquely represents a ticket.
I am trying to write a LINQ statement that shows me the number of tickets created per date. However, I cannot figure out how do this. Can someone show me how to do this?
Thank you!
I believe something like this will work:
var result = from ticket in TicketTable
group ticket by ticket.CreateDate.Date into g
select new {Date = g.Key, Count = g.Count() };
class Program
{
static void Main(string[] args)
{
List<Ticket> tickets = new List<Ticket>();
tickets.Add(new Ticket() { CreateDate = DateTime.Now, Id = 1 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(1), Id = 2 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(1), Id = 3 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(2), Id = 4 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(2), Id = 5 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(3), Id = 6 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(3), Id = 7 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(4), Id = 8 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(5), Id = 9 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(6), Id = 10 });
tickets.Add(new Ticket() { CreateDate = DateTime.Now.AddDays(7), Id = 11 });
var query = tickets.
GroupBy(t => t.CreateDate.Date).
Select(g => new { Date = g.Key, Count = g.Count() });
foreach (var g in query)
{
Console.WriteLine("{0} - {1}", g.Date, g.Count);
}
/* Outputs:
7/24/2010 12:00:00 AM - 1
7/25/2010 12:00:00 AM - 2
7/26/2010 12:00:00 AM - 2
7/27/2010 12:00:00 AM - 2
7/28/2010 12:00:00 AM - 1
7/29/2010 12:00:00 AM - 1
7/30/2010 12:00:00 AM - 1
7/31/2010 12:00:00 AM - 1 */
}
class Ticket
{
public int Id { get; set; }
public DateTime CreateDate { get; set; }
}
}
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