C#, LINQ : 取得前幾筆資料

  1. using System;
  2. using System.Collections.Generic;
  3. using System.Linq;
  4.  
  5. class Program
  6. {
  7. static void Main()
  8. {
  9. List<Person> people = new List<Person>
  10. {
  11. new Person { Id = 1, Name = "約翰史密斯", Age = 35 },
  12. new Person { Id = 2, Name = "簡道", Age = 28 },
  13. new Person { Id = 3, Name = "約翰強生", Age = 42 },
  14. new Person { Id = 4, Name = "愛麗絲強森", Age = 31 },
  15. new Person { Id = 5, Name = "鮑勃史密斯", Age = 40 },
  16. new Person { Id = 6, Name = "傑克強森", Age = 29 },
  17. };
  18.  
  19. var query = from person in people
  20. where person.Age >= 30 && person.Name.StartsWith("約翰")
  21. orderby person.Age descending
  22. select new
  23. {
  24. Id = person.Id,
  25. Name = person.Name,
  26. Age = person.Age
  27. };
  28.  
  29. var result = query.Take(5).ToList();
  30.  
  31. foreach (var person in result)
  32. {
  33. Console.WriteLine($"編號:{person.Id},姓名:{person.Name},年齡:{person.Age}");
  34. }
  35. }
  36. }
  37.  
  38. public class Person
  39. {
  40. public int Id { get; set; }
  41. public string Name { get; set; }
  42. public int Age { get; set; }
  43. }
  44.  

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