1using System;
 2using System.Data;
 3using System.Data.SqlClient;
 4using System.Collections;
 5using MessageBoard7.Classes;
 6
 7namespace MessageBoard7.SQLServerDAL
 8...{
 9    /**//// <summary>
10    /// SQLServer数据库中Messages表操作类。
11    /// </summary>
12    
13    public class Messages : MessageBoard7.IDAL.IMessages
14    ...{
15        public Messages()
16        ...{
17        }
18        private const string SQL_SELECT_MESSAGES = "SELECT MessageId,Content,PostTime FROM Messages ORDER BY MessageId DESC";
19        private const string SQL_INSERT_MESSAGES = "INSERT INTO Messages(Content,PostTime) values (@Content,@PostTime)";
20        private const string PARM_CONTENT = "@Content";
21        private const string PARM_POSTTIME = "@PostTime";
22        private const string SQL_SELECT_MESSAGES_TODAY = "SELECT MessageId,Content,PostTime FROM Messages WHERE PostTime>=@From AND PostTime<@To ORDER BY MessageId DESC";
23        private const string PARM_FROM = "@From";
24        private const string PARM_TO = "@To";
25        //获取所有留言
26        public MessagesInfo[] GetMessages()
27        ...{
28            ArrayList arrMessagesInfo = new ArrayList();
29            //调用SQLHelper类的ExecuteReader方法读出所有留言信息
30            SqlDataReader dr = SQLHelper.ExecuteReader(SQLHelper.CONN_STRING, CommandType.Text, SQL_SELECT_MESSAGES, null);
31            while(dr.Read())
32            ...{
33                MessagesInfo messagesInfo = new MessagesInfo();
34                messagesInfo.MessageId = (int)dr["MessageId"];
35                messagesInfo.Content = (string)dr["Content"];
36                messagesInfo.PostTime = (DateTime)dr["PostTime"];
37                arrMessagesInfo.Add(messagesInfo);
38            }
39            //将集合类型转化为数组
40            return (MessagesInfo[])arrMessagesInfo.ToArray(typeof(MessagesInfo));
41        }
42        //获取当天留言
43        public MessagesInfo[] GetMessages(DateTime from, DateTime to)
44        ...{
45            ArrayList arrMessagesInfo = new ArrayList();
46            SqlParameter[] parms = ...{
47                new SqlParameter(PARM_FROM, SqlDbType.DateTime),
48                new SqlParameter(PARM_TO, SqlDbType.DateTime)
49            };
50            parms[0].Value = from;
51            parms[1].Value = to;
52            //调用SQLHelper类的ExecuteReader方法当天所有留言信息
53            SqlDataReader dr = SQLHelper.ExecuteReader(SQLHelper.CONN_STRING, CommandType.Text, SQL_SELECT_MESSAGES_TODAY, parms);
54            while(dr.Read())
55            ...{
56                MessagesInfo messagesInfo = new MessagesInfo();
57                messagesInfo.MessageId = (int)dr["MessageId"];
58                messagesInfo.Content = (string)dr["Content"];
59                messagesInfo.PostTime = (DateTime)dr["PostTime"];
60                arrMessagesInfo.Add(messagesInfo);
61            }
62            //将集合类型转化为数组
63            return (MessagesInfo[])arrMessagesInfo.ToArray(typeof(MessagesInfo));
64        }
65        //将单条留言信息存入数据库
66        public void SaveMessage(MessagesInfo messagesInfo)
67        ...{
68            string content = messagesInfo.Content.Trim();
69            DateTime dt = DateTime.Now;
70            SqlParameter[] parms = ...{
71                new SqlParameter(PARM_CONTENT, SqlDbType.NText),
72                new SqlParameter(PARM_POSTTIME, SqlDbType.DateTime)
73            };
74            parms[0].Value = content;
75            parms[1].Value = dt;
76            //调用SQLHelper类的ExecuteNonQuery方法执行插入操作
77            SQLHelper.ExecuteNonQuery(SQLHelper.CONN_STRING, CommandType.Text, SQL_INSERT_MESSAGES, parms);
78        }
79        
80        
81        
82    }
83}
84