Distinct 实现自定义去重

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace wpfDistinct
{
    class DataCompare : IEqualityComparer<DateTime>
    {

        public bool Equals(DateTime x, DateTime y)
        {
            return x.Hour == y.Hour;
        }

        public int GetHashCode(DateTime obj)
        {
            return (obj.Year + obj.Month + obj.Day + obj.Hour).ToString().GetHashCode();

        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace wpfDistinct
{
    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            Random rand = new Random();
            List<DateTime> list = new List<DateTime>();
            for (int i = 0; i < 100; i++)
            {
                list.Add(new DateTime(2016, rand.Next(1, 12), rand.Next(1, 31), rand.Next(1, 12),rand.Next(1,59),rand.Next(1,59)));
            }
            if (null != list)
            {
                List<DateTime> list3 = list.Distinct(new DataCompare()).ToList();
              
                if (null != list3)
                {
                    List<List<DateTime>> collcetion = new List<List<DateTime>>();
                    foreach (DateTime time in list3)
                    {
                        collcetion.Add(list.Where(i => i.Month==time.Month&& i.Day == time.Day&&i.Hour==time.Hour).ToList());
                    }
                }
               
               
            }

        }
    }
}

Distinct 要实现IEqualityComparer<DateTime> 这个接口才能自定义
hashCode的精度到那个地方，就可以以那种精度进行去重