//引入命名空间
using System;
using System.Diagnostics;
   class MyEventlogClass
   {
      public static void Main()
      {
         String myEventType=null;
         // Associate the instance of 'EventLog' with local System Log.
         EventLog myEventLog = new EventLog("System", ".");
         Console.WriteLine("1:Error");
         Console.WriteLine("2:Information");
         Console.WriteLine("3:Warning");
         Console.WriteLine("Select the Event Type");
         int myOption=Convert.ToInt32(Console.ReadLine());
         switch(myOption)
         {
            case 1:  myEventType="Error";
                     break;
            case 2:  myEventType="Information";
                     break;
            case 3:  myEventType="Warning";
                     break;
            default: break;
         }

            EventLogEntryCollection myLogEntryCollection=myEventLog.Entries;
            int myCount =myLogEntryCollection.Count;
            // Iterate through all 'EventLogEntry' instances in 'EventLog'.
            for(int i=myCount-1;i>-1;i--)
            {
               EventLogEntry myLogEntry = myLogEntryCollection[i];
               // Select the entry having desired EventType.
               if(myLogEntry.EntryType.ToString().Equals(myEventType))
               {
                  // Display Source of the event.
                  Console.WriteLine(myLogEntry.Source
                     +" was the source of last event of type "
                     +myLogEntry.EntryType);
                  return;
               }
            }
         }
   }