如何在 C# 中使用 Comparison 委托对复杂类型列表进行排序?


List 类的 Sort() 方法的重载需要将 Comparison 委托作为参数传递。

public void Sort(Comparison<T> comparison)

CompareTo 返回一个整数,指示该实例的值是否小于、等于或大于指定对象的值或其他 Int16 实例。

在 C# 中,Int16.CompareTo() 方法用于将该实例与指定对象或另一个 Int16 实例进行比较。

示例

class Program{
   public static void Main(){
      Employee Employee1 = new Employee(){
         ID = 101,
         Name = "Mark",
         Salary = 4000
      };
      Employee Employee2 = new Employee(){
         ID = 103,
         Name = "John",
         Salary = 7000
      };
      Employee Employee3 = new Employee(){
         ID = 102,
         Name = "Ken",
         Salary = 5500
      };
      List<Employee> listEmployees = new List<Employee>();
      listEmployees.Add(Employee1);
      listEmployees.Add(Employee2);
      listEmployees.Add(Employee3);
      Console.WriteLine("Employees before sorting");
      foreach (Employee Employee in listEmployees){
         Console.WriteLine(Employee.ID);
      }
      listEmployees.Sort((x, y) => x.ID.CompareTo(y.ID));
      Console.WriteLine("Employees after sorting by ID");
      foreach (Employee Employee in listEmployees){
         Console.WriteLine(Employee.ID);
      }
      listEmployees.Reverse();
      Console.WriteLine("Employees in descending order of ID");
      foreach (Employee Employee in listEmployees){
         Console.WriteLine(Employee.ID);
      }
   }
   // Approach 1 - Step 1
   // Method that contains the logic to compare Employees
   private static int CompareEmployees(Employee c1, Employee c2){
      return c1.ID.CompareTo(c2.ID);
   }
}
public class Employee{
   public int ID { get; set; }
   public string Name { get; set; }
   public int Salary { get; set; }
}

输出

Employees before sorting
101
103
102
Employees after sorting by ID
101
102
103
Employees in descending order of ID
103
102
101

更新于:19-Aug-2020

465 次浏览

开启你的 职业 生涯

完成课程获得认证

开始
广告