Distinct 实现自定义去重

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 
 7 namespace wpfDistinct
 8 {
 9     class DataCompare : IEqualityComparer<DateTime>
10     {
11 
12         public bool Equals(DateTime x, DateTime y)
13         {
14             return x.Hour == y.Hour;
15         }
16 
17         public int GetHashCode(DateTime obj)
18         {
19             return (obj.Year + obj.Month + obj.Day + obj.Hour).ToString().GetHashCode();
20 
21         }
22     }
23 }

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6 using System.Windows;
 7 using System.Windows.Controls;
 8 using System.Windows.Data;
 9 using System.Windows.Documents;
10 using System.Windows.Input;
11 using System.Windows.Media;
12 using System.Windows.Media.Imaging;
13 using System.Windows.Navigation;
14 using System.Windows.Shapes;
15 
16 namespace wpfDistinct
17 {
18     /// <summary>
19     /// MainWindow.xaml 的交互逻辑
20     /// </summary>
21     public partial class MainWindow : Window
22     {
23         public MainWindow()
24         {
25             InitializeComponent();
26 
27             Random rand = new Random();
28             List<DateTime> list = new List<DateTime>();
29             for (int i = 0; i < 100; i++)
30             {
31                 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)));
32             }
33             if (null != list)
34             {
35                 List<DateTime> list3 = list.Distinct(new DataCompare()).ToList();
36               
37                 if (null != list3)
38                 {
39                     List<List<DateTime>> collcetion = new List<List<DateTime>>();
40                     foreach (DateTime time in list3)
41                     {
42                         collcetion.Add(list.Where(i => i.Month==time.Month&& i.Day == time.Day&&i.Hour==time.Hour).ToList());
43                     }
44                 }
45                
46                
47             }
48 
49         }
50     }
51 }

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