在c#中利用委托进行冒泡排序

Question

如何在c#中利用委托进行冒泡排序，下面我的这个代码有什么错误请各位高手指正：
Employee类    class Employee
    {
        private string name;
        private decimal salary;        public Employee(string name,decimal salary)
        {
            this.name=name;
            this.salary=salary;
        }        public override string ToString()
        {
            return string.Format("{0},{1:c}",name,salary);
        }        public static bool Comparison(object x, object y)
        {
            Employee e1 = (Employee)x;
            Employee e2 = (Employee)y;
            //return (e1.salary < e2.salary);
            return e1.salary < e2.salary;
        }
    }
BubbleSorter类: class BubbleSorter
    {
        static public void Sort(object[] sortArray, Comparison comparison) 
        {
            for (int i = 0; i < sortArray.Length; i++) 
            {
                for (int j = i + 1; j < sortArray.Length; j++)
                {
                    if (comparison(sortArray[j],sortArray[i])) 
                    {
                        object temp = sortArray[j];
                        sortArray[j] = sortArray[i];
                        sortArray[i] = temp;
                    }
                }
            }
        }
    }调用
 Employee[] employees =
            { 
                new Employee("Bugs Bunny",2000),
                new Employee("Elmer Fudd",10000),
                new Employee("Daffy Duck",250000),
                new Employee("Wiley Coyote",(decimal)1000000.38),
                new Employee("Foghorn Leghorn",23000),
                new Employee("RoadRunner",5000)
            };            //BubbleSorter.Sort(employees,Employee.CompareSalary);            BubbleSorter.Sort(employees,Employee.Comparison);
            
            foreach (var employee in employees)
            {
                Console.WriteLine(employee);
            }为什么会报：
错误 1 与“DelegatDemo.BubbleSorter.Sort(object[], Comparison)”最匹配的重载方法具有一些无效参数 E:\C#\vs08\Number\DelegatDemo\DelegatDemo\Program.cs 99 13 DelegatDemo错误 2 参数“2”: 无法从“方法组”转换为“Comparison” E:\C#\vs08\Number\DelegatDemo\DelegatDemo\Program.cs 99 41 DelegatDemo请各位高手指正，多谢！！！！

Answer 1

    class Employee
  {
      private string name;
      private decimal salary;      public Employee(string name,decimal salary)
      {
          this.name=name;
          this.salary=salary;
      }      public override string ToString()
      {
        return string.Format("{0},{1:c}",name,salary);
      }      public static bool Comparison(object x, object y)
      {
          Employee e1 = (Employee)x;
          Employee e2 = (Employee)y;
          //return (e1.salary < e2.salary);
          return e1.salary < e2.salary;
      }
  } class BubbleSorter
  {
     static public void Sort(object[] sortArray)  
      {
          for (int i = 0; i < sortArray.Length; i++)  
          {
              for (int j = i + 1; j < sortArray.Length; j++)
              {
                  if (Employee.Comparison(sortArray[j], sortArray[i]))  
                  {
                      object temp = sortArray[j];
                      sortArray[j] = sortArray[i];
                      sortArray[i] = temp;
                  }
              }
          }
      }
  }//invoke            Employee[] employees =
          {  
          new Employee("Bugs Bunny",2000),
          new Employee("Elmer Fudd",10000),
          new Employee("Daffy Duck",250000),
          new Employee("Wiley Coyote",(decimal)1000000.38),
          new Employee("Foghorn Leghorn",23000),
          new Employee("RoadRunner",5000)
          };            //BubbleSorter.Sort(employees,Employee.CompareSalary);            BubbleSorter.Sort(employees);            foreach (var employee in employees)
            {
                Console.WriteLine(employee);
            }

Answer 2

如果非要static public void Sort(object[] sortArray, Comparison comparison)  这么写 
你要把Comparison从Employee中分离出来 定义一个类 然后定义static比较方法例：
快排public interface IComp
{
int cmp(object o1, object o2);
}public class Int32Comp : IComp
{public Int32 cmp(object o1, object o2)
{
  Int32 i1 = Convert.ToInt32(o1);
  Int32 i2 = Convert.ToInt32(o2);  if (i1 < i2)
  {
    return -1;
  }
  else if (i1 == i2)
  {
    return 0;
  }
  else
  {
    return 1;
  }
}
}public class Quicksort
{
  private static Random rd = new Random();  public static void Sort<T>(T[] v, int left, int right, IComp cmp)
  {
    int i, last;    if (left >= right)
      return;    Swap<T>(v, left, rd.Next(left, right + 1));
    last = left;    for (i = left + 1; i < right + 1; i++)
    {
      if (cmp.cmp(v[i], v[left]) < 0)
      {
         Swap(v, ++last, i);
      }
     }     Swap<T>(v, left, last);
     Sort<T>(v, left, last - 1, cmp);
     Sort<T>(v, last + 1, right, cmp);
   }   public static void Swap<T>(T[] v, int i, int j)
   {
     T temp;     temp = v[i];
     v[i] = v[j];
     v[j] = temp;
   }
}
class Program
{
  static void Main(string[] args)
  {    Int32[] arr = {101, 11, 2, 7, 4, 5, 3, 30};
    Quicksort.Sort(arr, 0, arr.Length - 1, new Int32Comp());    foreach (Int32 i in arr)
    {
       Console.WriteLine(i);
    }
  }
}
from http://www.cnblogs.com/Peter-Zhang/articles/1982846.html

Answer 3

你没有声明委托
  public delegate bool  Comparison(object x,object y);

Answer 4

    public delegate bool Comparison<Type>(Type obj1, Type obj2);
    class Program
    {
        static void Main(string[] args)
        {
            Employee[] employees =
            {
                new Employee("Bugs Bunny",2000),
                new Employee("Elmer Fudd",10000),
                new Employee("Daffy Duck",250000),
                new Employee("Wiley Coyote",(decimal)1000000.38),
                new Employee("Foghorn Leghorn",23000),
                new Employee("RoadRunner",5000)
            };
            BubbleSorter.Sort<Employee>(employees, Employee.Comparison);            foreach (var employee in employees)
            {
                Console.WriteLine(employee);
            }
        }
    }    class Employee
    {
        private string name;
        private decimal salary;        public Employee(string name, decimal salary)
        {
            this.name = name;
            this.salary = salary;
        }        public override string ToString()
        {
            return string.Format("{0},{1:c}", name, salary);
        }        public static bool Comparison(Employee x, Employee y)
        {
            return x.salary < y.salary;
        }
    }
    class BubbleSorter
    {
        static public void Sort<Type>(Type[] sortArray, Comparison<Type> comparison)
        {            for (int i = 0; i < sortArray.Length; i++)
            {
                for (int j = i + 1; j < sortArray.Length; j++)
                {
                    if (comparison(sortArray[j], sortArray[i]))
                    {
                        Type temp = sortArray[j];
                        sortArray[j] = sortArray[i];
                        sortArray[i] = temp;
                    }
                }            }
        }
    }

Answer 5

Comparison在编译时被识别成《public static bool Comparison(object x, object y)》这类的方法

Answer 6

//测试<按名字排>
        BubbleSorter.Sort<Employee>(employees, Employee.Comparison_Name);//按名字排的方法
        public static bool Comparison_Name(Employee x, Employee y)
        {
            return x.name.CompareTo( y.name)<0;
        }

Answer 7

class Employee
    {
        private string name;
        private decimal salary;        public Employee(string name, decimal salary)
        {
            this.name = name;
            this.salary = salary;
        }        public override string ToString()
        {
            return string.Format("{0},{1:c}", name, salary);
        }        public static bool Comparison(object x, object y)
        {
            Employee e1 = (Employee)x;
            Employee e2 = (Employee)y;
            return e1.salary < e2.salary;
        }
    }    class BubbleSorter
    {
        static public void Sort(object[] sortArray)
        {
            for (int i = 0; i < sortArray.Length; i++)
            {
                for (int j = i + 1; j < sortArray.Length; j++)
                {
                    if (Employee.Comparison(sortArray[j], sortArray[i]))
                    {
                        object temp = sortArray[j];
                        sortArray[j] = sortArray[i];
                        sortArray[i] = temp;
                    }
                }
            }
        }
    }