Today , I was required to order a list of records based on a Name and then ID .
A simple one but i did spend some time on how to do it with Lambda Expression in C# .
How to order by multiple columns using Lambas and LINQ in C# ?
C# provides the OrderBy,OrderByDescending,ThenBy,ThenByDescending .
You can use them in your lambda expression to order the records as per your requirement .
Assuming your list is “Phones” and contains the following data …
public class Phone { public int ID { get; set; } public string Name { get; set; } } public class Phones : List { public Phones() { Add(new Phone { ID = 1, Name = "Windows Phone 7" }); Add(new Phone { ID = 5, Name = "iPhone" }); Add(new Phone { ID = 2, Name = "Windows Phone 7" }); Add(new Phone { ID = 3, Name = "Windows Mobile 6.1" }); Add(new Phone { ID = 6, Name = "Android" }); Add(new Phone { ID = 10, Name = "BlackBerry" }); } }
If you were to use LINQ Query , the query will look like the one below
dataGridView1.DataSource = (from m in new Phones() orderby m.Name, m.ID select m).ToList();
Simple isn’t it ? It very simple using Lamba expression too 🙂
Your Lambda’s expression for the above LINQ query will look like the one below
dataGridView1.DataSource = new Phones().OrderByDescending(a => a.Name).ThenByDescending(a => a.ID) .ToList();
1 Comment
this was very helpful. keep up the goodwork.