Question

有我的专栏

Id | date | location

和一些行：

1 | 2016/09/08 14:02:08 | NY
1 | 2016/09/08 14:03:08 | CA
1 | 2016/09/08 14:05:08 | SI
1 | 2016/09/08 14:07:05 | NY
1 | 2016/09/08 14:07:09 | NY
1 | 2016/09/08 14:07:22 | NY
1 | 2016/09/08 14:09:08 | SI
1 | 2016/09/08 14:23:08 | NY
1 | 2016/09/08 14:25:08 | LA

我想知道：

"where was user at least every 5 minutes"

所以我的结果是：

1 | 2016/09/08 14:02:08 | NY
1 | 2016/09/08 14:07:09 | NY
1 | 2016/09/08 14:23:08 | NY

我不希望我的搜索结果中有更多行。

所以，我该怎么做？任何解决方案，例如＆＃34; SQL Query＆＃34;，＆＃34; LinQ Expression＆＃34;，＆＃34; C＃code＆＃34;，...将会有所帮助。

谢谢你：）

Answer 1

考虑到班级：

public class LocationInformation
{
    public int ID { get; set; }
    public DateTime Date { get; set; }
    public string Location { get; set; }

    public override string ToString()
    {
        return String.Format("Guy with ID : ({0}), was near {1} at {2}", ID, Location, Date);
    }
}

功能：

public static void Locate(List<LocationInformation> myInformations, int id)
{
    DateTime lastCheck = DateTime.MinValue;
    foreach (LocationInformation locationInformation in myInformations.Where(i => i.ID == id).OrderBy(i => i.Date))
    {
        // Less than 5 min check
        if (locationInformation.Date < lastCheck.AddMinutes(5))
        {
            continue;
        }
        lastCheck = locationInformation.Date;
        Console.Out.WriteLine(locationInformation);
    }
}

这将完成工作。

Answer 2

试试这个

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;

namespace ConsoleApplication1
{
    public class Program
    {

        public static void Main()
        {
            string[] inputs = { 
                "1 | 2016/09/08 14:02:08 | NY",
                "1 | 2016/09/08 14:03:08 | CA",
                "1 | 2016/09/08 14:05:08 | SI",
                "1 | 2016/09/08 14:07:05 | NY",
                "1 | 2016/09/08 14:07:09 | NY",
                "1 | 2016/09/08 14:07:22 | NY",
                "1 | 2016/09/08 14:09:08 | SI",
                "1 | 2016/09/08 14:23:08 | NY",
                "1 | 2016/09/08 14:25:08 | LA"
                             };

            DataTable dt = new DataTable();
            dt.Columns.Add("Id", typeof(int));
            dt.Columns.Add("date", typeof(DateTime));
            dt.Columns.Add("location", typeof(string));

            foreach (string input in inputs)
            {
                string[] splitRow = input.Split(new char[] {'|'});
                dt.Rows.Add( new object[] {
                    int.Parse(splitRow[0]),
                    DateTime.Parse(splitRow[1]),
                    splitRow[2].Trim()
                });
            }
            var groups = dt.AsEnumerable()
                .GroupBy(x => x.Field<string>("location"))
                .Select(x => new {
                    id = x.First().Field<int>("Id"),
                    location = x.First().Field<string>("location"),
                    times = x.Select(y => y.Field<DateTime>("date")).ToList()
                }).ToList();

            foreach (var group in groups)
            {
                DateTime lastTime = new DateTime();
                foreach (var date in group.times)
                {
                    if (lastTime.AddMinutes(5) <= date)
                    {
                        Console.WriteLine(string.Join(",",  new string[] { group.id.ToString(), group.location, date.ToString()}));
                        lastTime = date;
                    }

                }
            }
            Console.ReadLine();
        }

    }
}

报告日期列与差距

2 个答案: