数据库访问类小结

 1using System;
 2using System.Collections.Generic;
 3using System.Configuration;
 4using System.Data;
 5using System.Data.SqlClient;
 6
 7namespace NGuestBook.SQLServerDAL
 8{
 9    /// <summary>
10    /// SQLServer数据库操作助手
11    /// </summary>
12    public sealed class SQLServerDALHelper
13    {
14        /// <summary>
15        /// 用于连接SQLServer数据库的连接字符串，存于Web.config中
16        /// </summary>
17        private static readonly string _sqlConnectionString = ConfigurationManager.AppSettings["SQLServerConnectionString"];
18
19        /// <summary>
20        /// 执行SQL命令，不返回任何值
21        /// </summary>
22        /// <param name="sql">SQL命令</param>
23        public static void ExecuteSQLNonQurey(string sql)
24        {
25            SqlConnection connection = new SqlConnection(_sqlConnectionString);
26            SqlCommand command = new SqlCommand(sql,connection);
27            connection.Open();
28            command.ExecuteNonQuery();
29            connection.Close();
30        }
31
32        /// <summary>
33        /// 执行SQL命令，并返回SqlDataReader
34        /// </summary>
35        /// <param name="sql">SQL命令</param>
36        /// <returns>包含查询结果的SqlDataReader</returns>
37        public static SqlDataReader ExecuteSQLReader(string sql)
38        {
39            SqlConnection connection = new SqlConnection(_sqlConnectionString);
40            SqlCommand command = new SqlCommand(sql, connection);
41            connection.Open();
42            SqlDataReader sqlReader = command.ExecuteReader();
43            //connection.Close();
44
45            return sqlReader;
46        }
47
48        /// <summary>
49        /// 执行存储过程，不返回任何值
50        /// </summary>
51        /// <param name="storedProcedureName">存储过程名</param>
52        /// <param name="parameters">参数</param>
53        public static void ExecuteProcedureNonQurey(string storedProcedureName,IDataParameter[] parameters)
54        {
55            SqlConnection connection = new SqlConnection(_sqlConnectionString);
56            SqlCommand command = new SqlCommand(storedProcedureName,connection);
57            command.CommandType = CommandType.StoredProcedure;
58            if (parameters != null)
59            {
60                foreach (SqlParameter parameter in parameters)
61                {
62                    command.Parameters.Add(parameter);
63                }
64            }
65            connection.Open();
66            command.ExecuteNonQuery();
67            connection.Close();
68        }
69
70        /// <summary>
71        /// 执行存储，并返回SqlDataReader
72        /// </summary>
73        /// <param name="storedProcedureName">存储过程名</param>
74        /// <param name="parameters">参数</param>
75        /// <returns>包含查询结果的SqlDataReader</returns>
76        public static SqlDataReader ExecuteProcedureReader(string storedProcedureName,IDataParameter[] parameters)
77        {
78            SqlConnection connection = new SqlConnection(_sqlConnectionString);
79            SqlCommand command = new SqlCommand(storedProcedureName,connection);
80            command.CommandType = CommandType.StoredProcedure;
81            if (parameters != null)
82            {
83                foreach (SqlParameter parameter in parameters)
84                {
85                    command.Parameters.Add(parameter);
86                }
87            }
88            connection.Open();
89            SqlDataReader sqlReader = command.ExecuteReader();
90            //connection.Close();
91
92            return sqlReader;
93        }
94    }
95}

//访问存储过程，实现数据库操作、

 1using System;
  2using System.Collections.Generic;
  3using System.Text;
  4using System.Data;
  5using System.Data.SqlClient;
  6using NGuestBook.IDAL;
  7using NGuestBook.Entity;
  8
  9namespace NGuestBook.SQLServerDAL
 10{
 11    public class AdminDAL : IAdminDAL
 12    {
 13        /// <summary>
 14        /// 插入管理员
 15        /// </summary>
 16        /// <param name="admin">管理员实体类</param>
 17        /// <returns>是否成功</returns>
 18        public bool Insert(AdminInfo admin)
 19        {
 20            SqlParameter[] parameters =
 21                {
 22                    new SqlParameter("@Name",SqlDbType.NVarChar),
 23                    new SqlParameter("@Password",SqlDbType.NVarChar)
 24                };
 25            parameters[0].Value = admin.Name;
 26            parameters[1].Value = admin.Password;
 27            try
 28            {
 29                SQLServerDALHelper.ExecuteProcedureNonQurey("Pr_InsertAdmin", parameters);
 30                return true;
 31            }
 32            catch
 33            {
 34                return false;
 35            }
 36        }
 37
 38        /// <summary>
 39        /// 删除管理员
 40        /// </summary>
 41        /// <param name="id">欲删除的管理员的ID</param>
 42        /// <returns>是否成功</returns>
 43        public bool Delete(int id)
 44        {
 45            SqlParameter[] parameters =
 46                {
 47                    new SqlParameter("@ID",SqlDbType.Int)
 48                };
 49            parameters[0].Value = id;
 50            try
 51            {
 52                SQLServerDALHelper.ExecuteProcedureNonQurey("Pr_DeleteAdmin", parameters);
 53                return true;
 54            }
 55            catch
 56            {
 57                return false;
 58            }
 59        }
 60
 61        ///<summary>
 62        /// 更新管理员信息
 63        /// </summary>
 64        /// <param name="admin">管理员实体类</param>
 65        /// <returns>是否成功</returns>
 66        public bool Update(AdminInfo admin)
 67        {
 68            SqlParameter[] parameters =
 69                {
 70                    new SqlParameter("@ID",SqlDbType.Int),
 71                    new SqlParameter("@Name",SqlDbType.NVarChar),
 72                    new SqlParameter("@Password",SqlDbType.NVarChar)
 73                };
 74            parameters[0].Value = admin.ID;
 75            parameters[1].Value = admin.Name;
 76            parameters[2].Value = admin.Password;
 77            try
 78            {
 79                SQLServerDALHelper.ExecuteProcedureNonQurey("Pr_UpdateAdmin", parameters);
 80                return true;
 81            }
 82            catch
 83            {
 84                return false;
 85            }
 86        }
 87
 88        /// <summary>
 89        /// 按ID取得管理员信息
 90        /// </summary>
 91        /// <param name="id">管理员ID</param>
 92        /// <returns>管理员实体类</returns>
 93        public AdminInfo GetByID(int id)
 94        {
 95            SqlParameter[] parameters =
 96                {
 97                    new SqlParameter("@ID",SqlDbType.Int)
 98                };
 99            parameters[0].Value = id;
100            SqlDataReader dataReader = null;
101            try
102            {
103                dataReader = SQLServerDALHelper.ExecuteProcedureReader("GetAdminByID", parameters);
104                dataReader.Read();
105                AdminInfo admin = new AdminInfo();
106                admin.ID = (int)dataReader["ID"];
107                admin.Name = (string)dataReader["Name"];
108                admin.Password = (string)dataReader["Password"];
109
110                return admin;
111            }
112            catch
113            {
114                return null;
115            }
116            finally
117            {
118                dataReader.Close();
119            }
120        }
121
122        /// <summary>
123        /// 按用户名及密码取得管理员信息
124        /// </summary>
125        /// <param name="name">用户名</param>
126        /// <param name="password">密码</param>
127        /// <returns>管理员实体类，不存在时返回null</returns>
128        public AdminInfo GetByNameAndPassword(string name, string password)
129        {
130            SqlParameter[] parameters =
131                {
132                    new SqlParameter("@Name",SqlDbType.NVarChar),
133                    new SqlParameter("@Password",SqlDbType.NVarChar)
134                };
135            parameters[0].Value = name;
136            parameters[1].Value = password;
137            SqlDataReader dataReader = null;
138            try
139            {
140                dataReader = SQLServerDALHelper.ExecuteProcedureReader("GetAdminByNameAndPassword", parameters);
141                dataReader.Read();
142                AdminInfo admin = new AdminInfo();
143                admin.ID = (int)dataReader["ID"];
144                admin.Name = (string)dataReader["Name"];
145                admin.Password = (string)dataReader["Password"];
146
147                return admin;
148            }
149            catch
150            {
151                return null;
152            }
153            finally
154            {
155                dataReader.Close();
156            }
157        }
158
159        /// <summary>
160        /// 按管理员名取得管理员信息
161        /// </summary>
162        /// <param name="name">管理员名</param>
163        /// <returns>管理员实体类</returns>
164        public AdminInfo GetByName(string name)
165        {
166            SqlParameter[] parameters =
167                {
168                    new SqlParameter("@Name",SqlDbType.NVarChar)
169                };
170            parameters[0].Value = name;
171            SqlDataReader dataReader = null;
172            try
173            {
174                dataReader = SQLServerDALHelper.ExecuteProcedureReader("GetAdminByName", parameters);
175                dataReader.Read();
176                AdminInfo admin = new AdminInfo();
177                admin.ID = (int)dataReader["ID"];
178                admin.Name = (string)dataReader["Name"];
179                admin.Password = (string)dataReader["Password"];
180
181                return admin;
182            }
183            catch
184            {
185                return null;
186            }
187            finally
188            {
189                dataReader.Close();
190            }
191        }
192
193        /// <summary>
194        /// 取得全部管理员信息
195        /// </summary>
196        /// <returns>管理员实体类集合</returns>
197        public IList<AdminInfo> GetAll()
198        {
199            SqlDataReader dataReader = null;
200            try
201            {
202                dataReader = SQLServerDALHelper.ExecuteProcedureReader("GetAllAdmin", null);
203                IList<AdminInfo> adminCollection=new List<AdminInfo>();
204                while (dataReader.Read())
205                {
206                    AdminInfo admin = new AdminInfo();
207                    admin.ID = (int)dataReader["ID"];
208                    admin.Name = (string)dataReader["Name"];
209                    admin.Password = (string)dataReader["Password"];
210                    adminCollection.Add(admin);
211                }
212
213                return adminCollection;
214            }
215            catch
216            {
217                return null;
218            }
219            finally
220            {
221                dataReader.Close();
222            }
223        }
224    }
225}

///直接访问数据库实体

1using System;
  2using System.Collections.Generic;
  3using System.Text;
  4using System.Data;
  5using System.Data.OleDb;
  6using NGuestBook.IDAL;
  7using NGuestBook.Entity;
  8
  9namespace NGuestBook.AccessDAL
 10{
 11    public class AdminDAL : IAdminDAL
 12    {
 13        /// <summary>
 14        /// 插入管理员
 15        /// </summary>
 16        /// <param name="admin">管理员实体类</param>
 17        /// <returns>是否成功</returns>
 18        public bool Insert(AdminInfo admin)
 19        {
 20            string SQLCommand = "insert into [TAdmin]([Name],[Password]) values(@name,@password)";
 21            OleDbParameter[] parameters ={
 22                new OleDbParameter("name",admin.Name),
 23                new OleDbParameter("password",admin.Password)
 24            };
 25
 26            try
 27            {
 28                AccessDALHelper.ExecuteSQLNonQuery(SQLCommand, parameters);
 29                return true;
 30            }
 31            catch
 32            {
 33                return false;
 34            }
 35        }
 36
 37        /// <summary>
 38        /// 删除管理员
 39        /// </summary>
 40        /// <param name="id">欲删除的管理员的ID</param>
 41        /// <returns>是否成功</returns>
 42        public bool Delete(int id)
 43        {
 44            string SQLCommand = "delete from [TAdmin] where [ID]=@id";
 45            OleDbParameter[] parameters ={
 46                new OleDbParameter("id",id)
 47            };
 48
 49            try
 50            {
 51                AccessDALHelper.ExecuteSQLNonQuery(SQLCommand, parameters);
 52                return true;
 53            }
 54            catch
 55            {
 56                return false;
 57            }
 58        }
 59
 60        /// <summary>
 61        /// 更新管理员信息
 62        /// </summary>
 63        /// <param name="admin">管理员实体类</param>
 64        /// <returns>是否成功</returns>
 65        public bool Update(AdminInfo admin)
 66        {
 67            string SQLCommand = "update [TAdmin] set [Name]=@name,[Password]=@password where [ID]=@id";
 68            OleDbParameter[] parameters ={
 69                new OleDbParameter("id",admin.ID),
 70                new OleDbParameter("name",admin.Name),
 71                new OleDbParameter("password",admin.Password)
 72            };
 73
 74            try
 75            {
 76                AccessDALHelper.ExecuteSQLNonQuery(SQLCommand, parameters);
 77                return true;
 78            }
 79            catch
 80            {
 81                return false;
 82            }
 83        }
 84
 85        /// <summary>
 86        /// 按ID取得管理员信息
 87        /// </summary>
 88        /// <param name="id">管理员ID</param>
 89        /// <returns>管理员实体类</returns>
 90        public AdminInfo GetByID(int id)
 91        {
 92            string SQLCommand = "select * from [TAdmin] where [ID]=@id";
 93            OleDbParameter[] parameters ={
 94                new OleDbParameter("id",id)
 95            };
 96
 97            try
 98            {
 99                OleDbDataReader dataReader = AccessDALHelper.ExecuteSQLDataReader(SQLCommand, parameters);
100                if (!dataReader.HasRows)
101                {
102                    throw new Exception();
103                }
104
105                AdminInfo admin = new AdminInfo();
106                dataReader.Read();
107                admin.ID=(int)dataReader["ID"];
108                admin.Name=(string)dataReader["Name"];
109                admin.Password=(string)dataReader["Password"];
110
111                return admin;
112            }
113            catch
114            {
115                return null;
116            }
117        }
118
119        /// <summary>
120        /// 按用户名及密码取得管理员信息
121        /// </summary>
122        /// <param name="name">用户名</param>
123        /// <param name="password">密码</param>
124        /// <returns>管理员实体类，不存在时返回null</returns>
125        public AdminInfo GetByNameAndPassword(string name, string password)
126        {
127            string SQLCommand = "select * from [TAdmin] where [Name]=@name and [Password]=@password";
128            OleDbParameter[] parameters ={
129                new OleDbParameter("name",name),
130                new OleDbParameter("password",password),
131            };
132
133            try
134            {
135                OleDbDataReader dataReader = AccessDALHelper.ExecuteSQLDataReader(SQLCommand, parameters);
136                if (!dataReader.HasRows)
137                {
138                    throw new Exception();
139                }
140
141                AdminInfo admin = new AdminInfo();
142                dataReader.Read();
143                admin.ID = (int)dataReader["ID"];
144                admin.Name = (string)dataReader["Name"];
145                admin.Password = (string)dataReader["Password"];
146
147                return admin;
148            }
149            catch
150            {
151                return null;
152            }
153        }
154
155        /// <summary>
156        /// 按管理员名取得管理员信息
157        /// </summary>
158        /// <param name="name">管理员名</param>
159        /// <returns>管理员实体类</returns>
160        public AdminInfo GetByName(string name)
161        {
162            string SQLCommand = "select * from [TAdmin] where [Name]=@name";
163            OleDbParameter[] parameters ={
164                new OleDbParameter("name",name),
165            };
166
167            try
168            {
169                OleDbDataReader dataReader = AccessDALHelper.ExecuteSQLDataReader(SQLCommand, parameters);
170                if (!dataReader.HasRows)
171                {
172                    throw new Exception();
173                }
174
175                AdminInfo admin = new AdminInfo();
176                dataReader.Read();
177                admin.ID = (int)dataReader["ID"];
178                admin.Name = (string)dataReader["Name"];
179                admin.Password = (string)dataReader["Password"];
180
181                return admin;
182            }
183            catch
184            {
185                return null;
186            }
187        }
188
189        /// <summary>
190        /// 取得全部管理员信息
191        /// </summary>
192        /// <returns>管理员实体类集合</returns>
193        public IList<AdminInfo> GetAll()
194        {
195            string SQLCommand = "select * from [TAdmin]";
196            try
197            {
198                OleDbDataReader dataReader = AccessDALHelper.ExecuteSQLDataReader(SQLCommand, null);
199                if (!dataReader.HasRows)
200                {
201                    throw new Exception();
202                }
203
204                IList<AdminInfo> adminCollection = new List<AdminInfo>();
205                int i = 0;
206                while (dataReader.Read())
207                {
208                    AdminInfo admin = new AdminInfo();
209                    admin.ID = (int)dataReader["ID"];
210                    admin.Name = (string)dataReader["Name"];
211                    admin.Password = (string)dataReader["Password"];
212
213                    adminCollection.Add(admin);
214                    i++;
215                }
216
217                return adminCollection;
218            }
219            catch
220            {
221                return null;
222            }
223        }
224    }
225}