原创DB4o嵌入式开源数据库

此文原创，仅供参考。转载请注明出处！

Program类代码如下：

  1using System;
  2using System.Collections.Generic;
  3using System.Text;
  4
  5using System.IO;
  6using Db4objects.Db4o;
  7using Db4objects.Db4o.Query;
  8
  9namespace DB40DataBase
 10{
 11    class Program
 12    {
 13        static void Main(string[] args)
 14        {
 15            
 16            AccessDb4o();
 17            
 18        }
 19        public static void AccessDb4o()
 20        {
 21 
 22            IObjectContainer db = Db4oFactory.OpenFile("Db4oDemo.cod");
 23            {
 24                try
 25                {
 26                    //StoreSecondPilot(db);         //存储数值
 27                    if (File.Exists("Db4oDemo.cod") == false)
 28                    {
 29                        Console.WriteLine("没有找到数据文件！");
 30                        return;
 31
 32                    }
 33                    else
 34                    {
 35                        RetrieveAllPilots(db);          //查找数值
 36
 37                    }
 38              
 39                    
 40                }
 41                catch (Exception ex)
 42                {
 43                    Console.WriteLine(ex.Message);
 44                }
 45                finally
 46                {
 47                    db.Close();
 48                }
 49
 50            }
 51            
 52            
 53        }
 54
 55        //存储数值
 56        public static void StoreSecondPilot(IObjectContainer db)
 57        {
 58            Pilot pilot1 = new Pilot("Barrillo ", 99);
 59            Pilot pilot2 = new Pilot("Rubens ", 90);
 60            Pilot pilot3 = new Pilot("Runs ", 100);
 61
 62            db.Store(pilot1);
 63            db.Store(pilot2);
 64            db.Store(pilot3);
 65
 66            Console.WriteLine("Stored {0}", pilot1);
 67            Console.WriteLine("Stored {0}", pilot2);
 68            Console.WriteLine("Stored {0}", pilot3);
 69        }
 70
 71        //下面是查找数值的实现
 72        public static void RetrieveAllPilots(IObjectContainer db)
 73        {
 74            IObjectSet results = db.QueryByExample(typeof(Pilot));
 75            ListResult(results);
 76        }
 77
 78        //遍历IObjectSet中Polot中的各个对象
 79        public static void ListResult(IObjectSet result)
 80        {
 81            if (result.Count>0)
 82            {
 83                Console.WriteLine("共有{0}条数据,分别是", result.Count);
 84                foreach (object item in result)
 85                {
 86                    Console.WriteLine(item);
 87                }
 88
 89            }
 90            else
 91            {
 92                Console.WriteLine("没有数据");
 93
 94            }
 95            
 96        }
 97
 98    }
 99}
100

Pilot类代码如下：

 1using System;
 2using System.Collections.Generic;
 3using System.Text;
 4
 5namespace DB40DataBase
 6{
 7    class Pilot
 8    {
 9        string _name;
10        int _points;
11        public Pilot(string name, int points)
12        {
13            _name = name;
14            _points = points;
15        }
16        public string Name
17        {
18            get
19            {
20                return _name;
21            }
22        }
23
24        public int Points
25        {
26            get
27            {
28                return _points;
29            }
30        }
31        
32        public void AddPoints(int points)
33        {
34            _points += points;
35        }
36
37        override public string ToString()
38        {
39            return string.Format("{0}/{1}", _name, _points);
40        }
41    }
42}
43