Lambda 或 LINQ 到排序列表<employee>按班次，C#</employee>

Question

I have a List of Employee that I need to filter, and I'd like to see how to do this using a lambda and/or LINQ expression.

I want to return ALL of the Employees in the List, but I want them returned in order of Shift, Lastname, and Firstname.

List<Employee> empList = GetEmployeesInOtherCode();
// ...
int MAX_SHIFT = 5;
List<string> sortedNames = new List<string>(empList.Count);
for (int i = 0; i < MAX_SHIFT; i++) {
  List<string> localShift = new List<string>();
  for (int j = 0; j < empList.Count; j++) {
    Employee e = empList[j];
    if (e.Shift == i) {
      localShift.Add(string.Format("{0}, {1}", e.Lastname, e.Firstname));
    }
  }
  localShift.Sort();
  sortedNames.AddRange(localShift.ToArray());
}
foreach (string line in sortedNames) {
  Console.WriteLine(line);
}

EDIT: Jeez you guys are fast? What do you use to generate this stuff, Are you hand coding it? or is there a tool out there that helps?

Answer 1

var sortedNames = empList.Where(e => e.Shift >= 0 && e.Shift < MAX_SHIFT)
                         .OrderBy(e => e.Shift)
                         .ThenBy(e => e.LastName)
                         .ThenBy(e => e.FirstName)
                         .Select(e => string.Format("{0}, {1}", e.Lastname, e.Firstname))
                         .ToList();

Answer 2

For this I like query expression syntax better:

List<string> sortedNames = (from e in empList
                            orderby e.Shift, e.LastName, e.FirstName
                            select string.Format("{0}, {1}", 
                                                  e.Lastname, 
                                                  e.Firstname)).ToList();

Answer 3

OrderBy and ThenBy :

empList.OrderBy(e => e.Shift).ThenBy(e => e.LastName).ThenBy(e => e.FirstName);