Question

I have the following model

public class UserViewModel
    {
        public String CVR_Nummer { get; set; }
        public DateTime LastActivityDate { get; set; }
        public DateTime CreationDate { get; set; }
        public String FirmaNavn { get; set; }
        public int ProcentAnswered { get; set; }
    }

I create a List<UserViewModel> and try to sort it:

userviewmodel.OrderBy(x => x.ProcentAnswered);

It compiles, but the list doesnt get sorted. Howcome?

Answer 1

LINQ is side-effect free by design so it won’t change the input. Also it uses lazy execution, it won’t do anything till you try to reach the data. Re-assign the output to the list and it should work. Notice that I’m using ToList() method here because OrderBy() returns IEnumerable<UserViewModel> and it’s not evaluated till we try to get the items in it. We create a new list from this sequence using ToList() method and forcing the query to execute.

userviewmodel = userviewmodel.OrderBy(x => x.ProcentAnswered).ToList();