class test
  {
Random rnd=null;
public test(Random m_Rnd )
  {
rnd=m_Rnd;
}
  public void Time(){
  Console.WriteLine(rnd.Next(200));
  }
  }

------解决方案--------------------
C# code

test t1 = new test();
Thread.Sleep(100);
test t2 = new test();
Thread.Sleep(100);
test t3 = new test();

------解决方案--------------------
C# code
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;

namespace Cfeibulaqie
{
    class Program
    {
        public static void Main(string[] args)
        {           
            Random _Rnd = new Random();
            for (int i = 0; i < 5; i++)
            {
                Console.WriteLine(_Rnd.Next(200));
            }
            Console.WriteLine("///////////////////////////////////////////");
            test t1 = new test();
            Thread.Sleep(300);
            test t2 = new test();
            Thread.Sleep(300);
            test t3 = new test();
            for (int i = 0; i < 5; i++)
            {                
                    t1.Time();
                    
                    t2.Time();
                    
                    t3.Time();               
            }

            Console.ReadLine();
        }
        class test
        {
            Random m_Rnd = new Random();            
            public void Time()
            {
                Console.WriteLine(m_Rnd.Next(200));
            }
        }
    }

}