Orderby doesn't call Compare() of the provided comparer
.net, c#, linq
Solution
It doesn't work because you're not actually evaluating the `orderedEmployees` sequence. You need to force the evaluation using `ToList` or `ToArray`.
Linq uses deferred execution so defining your ordering query in:
IOrderedEnumerable<Employee> orderedEmployees = empList.OrderBy(x => x, eAsc);
does not do any work to actually order the input sequence. Only when you try to use the result of the query will the ordering be done.
Problem
Can anyone please explain why .net framework doesn't call compare method of my comparer when I use Enumerable.OrderBy. Whereas it does get called when I use List.Sort(). // The code below has been taken from another post on StackOverFlow.com ``` class Employee { public string Name { get; set; } public int Salary { get; set; } } class Employee_SortBySalaryByAscendingOrder : IComparer<Employee> { #region IComparer<Employee> Members public int Compare(Employee x, Employee y) { if (x.Salary > y.Salary) return 1; else if (x.Salary < y.Salary) return -1; else return 0; } #endregion } private void TestSort(object sender, EventArgs e) { List<Employee> empList = new List<Employee>() { new Employee { Name = "a", Salary = 14000 }, new Employee { Name = "b", Salary = 13000 } }; Employee_SortBySalaryByAscendingOrder eAsc = new Employee_SortBySalaryByAscendingOrder(); // Sort Employees by salary by ascending order. // Does not work IOrderedEnumerable<Employee> orderedEmployees = empList.OrderBy(x => x, eAsc); // Works empList.Sort(eAsc); } ```