static void Draw(){int count = 5000000;Console.WriteLine("test:{0} feeds", count);List<GoldCoinInfo> list = new List<GoldCoinInfo>();list.Add(new GoldCoinInfo { Id = 100, GoldValue = 5, LeftCount = count, TotalCount = count });var dic = new Dictionary<int, int>();int _index = 0;Stopwatch sw = new Stopwatch();sw.Restart();foreach (var gold in list){for (int j = 0; j < gold.LeftCount; j++){dic.Add(_index, gold.Id);_index++;}}sw.Stop();Console.WriteLine("step1:{0} ms", sw.ElapsedMilliseconds);sw.Restart();var prizeIndex2 = GenerateRandom(dic.Keys.Max(), 1).FirstOrDefault();Console.WriteLine("step3:{0} ms,value:{1}", sw.ElapsedMilliseconds, dic[prizeIndex2]);sw.Stop();}

  　　　　　var dic = new Dictionary<int, Tuple<int, int>>();int _index = 0;Stopwatch sw = new Stopwatch();sw.Restart();foreach (var gold in list){for (int j = 0; j < gold.LeftCount; j++){dic.Add(_index, new Tuple<int, int>(gold.Id, gold.GoldValue));_index++;}}

 　　/// <summary>/// sql函数的扩展类/// </summary>public static class SqlFunctionExtensions{#region 功能方法/// <summary>/// 在linq to entity中使用SqlServer.NEWID函数/// </summary>public static Guid NewId(){return Guid.NewGuid();}#endregion#region 扩展方法/// <summary>/// 随机排序扩展方法/// </summary>/// <typeparam name="T"></typeparam>/// <param name="source"></param>/// <returns></returns>public static IQueryable<T> OrderByNewId<T>(this IEnumerable<T> source){return source.AsQueryable().OrderBy(d => NewId());}#endregion}