C#自定义转换器的实现

namespace Study12_自定义数据类型转换.Common
{
    public class Singleton<T> where T : class
    {
        private static object _object = new object();

        private static T _instance;

        public static T Instance
        {
            get
            {
                if (_instance == null)
                {
                    lock (_object)
                    {
                        if (_instance == null)
                        {
                            _instance = Activator.CreateInstance<T>();
                        }
                        return _instance;
                    }
                }
                return _instance;
            }
        }
    }
}

public class DataConverter:Singleton<DataConverter>
{
    public Student GetStudent(Employee emp)
    {
        return (Student)emp;
    }

    public Employee GetEmployee(Student student)
    {
        return student;
    }
}

internal class Program
{
    static void Main(string[] args)
    {
       Employee employee= DataConverter.Instance.GetEmployee(new Student
        {
            Id = 1,
            Name = "小明"
        });
        employee.DoWork();
        Console.WriteLine("Hello, World!");

        //throw new NotImplementedException();
       
    }
}