【原创】利用Windows系统日志统计员工每天上下班考勤时间

利用Windows系统日志统计员工每天上下班考勤时间（命令行参数为统计月份）：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Diagnostics;



namespace ConsoleSysLogView

{

    class Program

    {

        static void Main(string[] args)

        {

            SystemLog log = new SystemLog();

            if (args.Length == 1)

            {

                int x = Convert.ToInt32(args[0]);

                log.PrintEventLog(x);

            }

            else

            {

                Console.WriteLine("Event count: " + log.Count);

                Console.WriteLine("QueryMessage: SysLogView.exe MonthNum");

            }



            if (Debugger.IsAttached) Console.ReadKey();

        }

    }



    public class SystemLog

    {

        private EventLogEntryCollection _eventCollection;

        private EventLog _systemEvent;



        public SystemLog()

        {

            _systemEvent = new EventLog();

            _systemEvent.Log = "System";

            _eventCollection = _systemEvent.Entries;

        }



        public void PrintEventLog(int month)

        {

            DateTime dateFrom = new DateTime(DateTime.Now.Year, month, 1);

            DateTime dateTo = dateFrom.AddMonths(1);



            DateTime dt = dateFrom;

            while (dt < dateTo)

            {

                IList<EventLogEntry> list = Events.Where(a => a.TimeGenerated.Date == dt.Date).OrderBy(a => a.TimeGenerated).ToList();

                if (list.Count > 0)

                {

                    Console.WriteLine();

                    Console.WriteLine(GetLogEntryText(list[0]));

                    if (list.Count > 1)

                    {

                        int l = list.Count - 1;

                        Console.WriteLine(GetLogEntryText(list[l]));

                    }

                }



                dt = dt.AddDays(1);

            }

        }



        private string GetLogEntryText(EventLogEntry entry)

        {

            return string.Format("{0} {1:yyyy-MM-dd HH:mm} 来源：{2} 事件ID：{3}", entry.EntryType, entry.TimeGenerated.ToString("yyyy-MM-dd HH:mm"), entry.Source, entry.InstanceId);

        }



        private IList<EventLogEntry> _events;

        public IList<EventLogEntry> Events

        {

            get

            {

                if (_events == null)

                {

                    _events = new List<EventLogEntry>();



                    for (int i = 0; i < _eventCollection.Count; i++)

                    {

                        EventLogEntry entry = _eventCollection[i];

                        _events.Add(entry);

                        if (i % 1000 == 0) Console.Write(".");

                    }

                }



                return _events;

            }

        }



        public int Count

        {

            get { return Events.Count; }

        }



    }

}