Pourquoi ne pas le mesurer:
class Program
{
class NameComparer : IComparer<string>
{
public int Compare(string x, string y)
{
return string.Compare(x, y, true);
}
}
class Person
{
public Person(string id, string name)
{
Id = id;
Name = name;
}
public string Id { get; set; }
public string Name { get; set; }
}
static void Main()
{
List<Person> persons = new List<Person>();
persons.Add(new Person("P005", "Janson"));
persons.Add(new Person("P002", "Aravind"));
persons.Add(new Person("P007", "Kazhal"));
Sort(persons);
OrderBy(persons);
const int COUNT = 1000000;
Stopwatch watch = Stopwatch.StartNew();
for (int i = 0; i < COUNT; i++)
{
Sort(persons);
}
watch.Stop();
Console.WriteLine("Sort: {0}ms", watch.ElapsedMilliseconds);
watch = Stopwatch.StartNew();
for (int i = 0; i < COUNT; i++)
{
OrderBy(persons);
}
watch.Stop();
Console.WriteLine("OrderBy: {0}ms", watch.ElapsedMilliseconds);
}
static void Sort(List<Person> list)
{
list.Sort((p1, p2) => string.Compare(p1.Name, p2.Name, true));
}
static void OrderBy(List<Person> list)
{
var result = list.OrderBy(n => n.Name, new NameComparer()).ToArray();
}
}
Sur mon ordinateur, une fois compilé en mode Release, ce programme imprime:
Sort: 1162ms
OrderBy: 1269ms
METTRE À JOUR:
Comme suggéré par @Stefan, voici les résultats du tri d'une grande liste moins de fois:
List<Person> persons = new List<Person>();
for (int i = 0; i < 100000; i++)
{
persons.Add(new Person("P" + i.ToString(), "Janson" + i.ToString()));
}
Sort(persons);
OrderBy(persons);
const int COUNT = 30;
Stopwatch watch = Stopwatch.StartNew();
for (int i = 0; i < COUNT; i++)
{
Sort(persons);
}
watch.Stop();
Console.WriteLine("Sort: {0}ms", watch.ElapsedMilliseconds);
watch = Stopwatch.StartNew();
for (int i = 0; i < COUNT; i++)
{
OrderBy(persons);
}
watch.Stop();
Console.WriteLine("OrderBy: {0}ms", watch.ElapsedMilliseconds);
Impressions:
Sort: 8965ms
OrderBy: 8460ms
Dans ce scénario, il semble que OrderBy fonctionne mieux.
UPDATE2:
Et en utilisant des noms aléatoires:
List<Person> persons = new List<Person>();
for (int i = 0; i < 100000; i++)
{
persons.Add(new Person("P" + i.ToString(), RandomString(5, true)));
}
Où:
private static Random randomSeed = new Random();
public static string RandomString(int size, bool lowerCase)
{
var sb = new StringBuilder(size);
int start = (lowerCase) ? 97 : 65;
for (int i = 0; i < size; i++)
{
sb.Append((char)(26 * randomSeed.NextDouble() + start));
}
return sb.ToString();
}
Rendements:
Sort: 8968ms
OrderBy: 8728ms
Still OrderBy est plus rapide