当前文件： myBBS/App_Code/DataAccessLayer/Database.cs[5K，2009-6-12 11:48:08]，打开代码结构图

		            
  1using System;
  2using System.ComponentModel;
  3using System.Collections;
  4using System.Diagnostics;
  5using System.Data;
  6using System.Data.SqlClient;
  7using System.Configuration;
  8
  9namespace MyBBS.DataAccessLayer
 10...{
 11    /**//// <summary>
 12    /// 类，用于数据访问的类。
 13    /// </summary>
 14    public class Database : IDisposable 
 15    ...{
 16        /**//// <summary>
 17        /// 保护变量，数据库连接。
 18        /// </summary>
 19        protected SqlConnection Connection;
 20
 21        /**//// <summary>
 22        /// 保护变量，数据库连接串。
 23        /// </summary>
 24        protected String ConnectionString;
 25        
 26        /**//// <summary>
 27        /// 构造函数。
 28        /// </summary>
 29        /// <param name="DatabaseConnectionString">数据库连接串</param>
 30        public Database()
 31        ...{
 32            ConnectionString = ConfigurationManager.AppSettings["DBConnectionString"];
 33        }
 34
 35        /**//// <summary>
 36        /// 构造函数。
 37        /// </summary>
 38        /// <param name="pDatabaseConnectionString">数据库连接串</param>
 39        public Database(string pDatabaseConnectionString)
 40        ...{
 41            ConnectionString = pDatabaseConnectionString;
 42        }
 43
 44        /**//// <summary>
 45        /// 析构函数，释放非托管资源
 46        /// </summary>
 47        ~Database()
 48        ...{
 49            try
 50            ...{
 51                if (Connection != null)
 52                    Connection.Close();
 53            }
 54            catch...{}
 55            try
 56            ...{
 57                Dispose();
 58            }
 59            catch...{}
 60        }
 61
 62        /**//// <summary>
 63        /// 保护方法，打开数据库连接。
 64        /// </summary>
 65        protected void Open() 
 66        ...{
 67            if (Connection == null)
 68            ...{
 69                Connection = new SqlConnection(ConnectionString);
 70            }
 71            if (Connection.State.Equals(ConnectionState.Closed))
 72            ...{
 73                Connection.Open();
 74            }
 75        }
 76
 77        /**//// <summary>
 78        /// 公有方法，关闭数据库连接。
 79        /// </summary>
 80        public void Close() 
 81        ...{
 82            if (Connection != null)
 83                Connection.Close();
 84        }
 85
 86        /**//// <summary>
 87        /// 公有方法，释放资源。
 88        /// </summary>
 89        public void Dispose() 
 90        ...{
 91            // 确保连接被关闭
 92            if (Connection != null) 
 93            ...{
 94                Connection.Dispose();
 95                Connection = null;
 96            }                
 97        }
 98        
 99        /**//// <summary>
100        /// 公有方法，获取数据，返回一个SqlDataReader （调用后主意调用SqlDataReader.Close()）。
101        /// </summary>
102        /// <param name="SqlString">Sql语句</param>
103        /// <returns>SqlDataReader</returns>
104        public SqlDataReader GetDataReader(String SqlString)
105        ...{
106            Open();
107            SqlCommand cmd = new SqlCommand(SqlString,Connection);
108            return cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
109        }
110
111        /**//// <summary>
112        /// 公有方法，获取数据，返回一个DataSet。
113        /// </summary>
114        /// <param name="SqlString">Sql语句</param>
115        /// <returns>DataSet</returns>
116        public DataSet GetDataSet(String SqlString)
117        ...{
118            Open();
119            SqlDataAdapter adapter = new SqlDataAdapter(SqlString,Connection);
120            DataSet dataset = new DataSet();
121            adapter.Fill(dataset);
122            Close();
123            return dataset;
124        }
125
126        /**//// <summary>
127        /// 公有方法，获取数据，返回一个DataRow。
128        /// </summary>
129        /// <param name="SqlString">Sql语句</param>
130        /// <returns>DataRow</returns>
131        public DataRow GetDataRow(String SqlString)
132        ...{
133            DataSet dataset = GetDataSet(SqlString);
134            dataset.CaseSensitive = false;
135            if (dataset.Tables[0].Rows.Count>0)
136            ...{
137                return dataset.Tables[0].Rows[0];
138            }
139            else
140            ...{
141                return null;
142            }
143        }
144
145        /**//// <summary>
146        /// 公有方法，执行Sql语句。
147        /// </summary>
148        /// <param name="SqlString">Sql语句</param>
149        /// <returns>对Update、Insert、Delete为影响到的行数，其他情况为-1</returns>
150        public int ExecuteSQL(String SqlString)
151        ...{
152            int count = -1;
153            Open();
154            try
155            ...{
156                SqlCommand cmd = new SqlCommand(SqlString,Connection);
157                count = cmd.ExecuteNonQuery();
158            }
159            catch
160            ...{
161                count = -1;
162            }
163            finally
164            ...{
165                Close();
166            }
167            return count;
168        }
169
170        /**//// <summary>
171        /// 公有方法，执行一组Sql语句。
172        /// </summary>
173        /// <param name="SqlStrings">Sql语句组</param>
174        /// <returns>是否成功</returns>
175        public bool ExecuteSQL(ArrayList SqlStrings)
176        ...{
177            bool success = true;
178            Open();
179            SqlCommand cmd = new SqlCommand();
180            SqlTransaction trans = Connection.BeginTransaction();
181            cmd.Connection = Connection;
182            cmd.Transaction = trans;
183            try
184            ...{
185                foreach (String str in SqlStrings)
186                ...{
187                    cmd.CommandText = str;
188                    cmd.ExecuteNonQuery();
189                }
190                trans.Commit();
191            }
192            catch
193            ...{
194                success = false;
195                trans.Rollback();                
196            }
197            finally
198            ...{
199                Close();
200            }
201            return success;
202        }
203
204        /**//// <summary>
205        /// 公有方法，在一个数据表中插入一条记录。
206        /// </summary>
207        /// <param name="TableName">表名</param>
208        /// <param name="Cols">哈西表，键值为字段名，值为字段值</param>
209        /// <returns>是否成功</returns>
210        public bool Insert(String TableName,Hashtable Cols)
211        ...{
212            int Count = 0;
213
214            if (Cols.Count<=0)            
215            ...{
216                return true;
217            }
218
219            String Fields = " (";
220            String Values = " Values(";            
221            foreach(DictionaryEntry item in Cols)
222            ...{
223                if (Count!=0)
224                ...{
225                    Fields += ",";
226                    Values += ",";
227                }
228                Fields += item.Key.ToString();
229                Values += item.Value.ToString();
230                Count ++;
231            }
232            Fields += ")";
233            Values += ")";
234
235            String SqlString = "Insert into "+TableName+Fields+Values;
236
237            return Convert.ToBoolean(ExecuteSQL(SqlString));
238        }
239
240        /**//// <summary>
241        /// 公有方法，更新一个数据表。
242        /// </summary>
243        /// <param name="TableName">表名</param>
244        /// <param name="Cols">哈西表，键值为字段名，值为字段值</param>
245        /// <param name="Where">Where子句</param>
246        /// <returns>是否成功</returns>
247        public bool Update(String TableName,Hashtable Cols,String Where)
248        ...{
249            int Count = 0;
250            if (Cols.Count<=0)            
251            ...{
252                return true;
253            }
254            String Fields = " ";
255            foreach(DictionaryEntry item in Cols)
256            ...{
257                if (Count!=0)
258                ...{
259                    Fields += ",";
260                }
261                Fields += item.Key.ToString();
262                Fields += "=";
263                Fields += item.Value.ToString();
264                Count ++;
265            }
266            Fields += " ";
267
268            String SqlString = "Update "+TableName+" Set "+Fields+Where;
269
270            return Convert.ToBoolean(ExecuteSQL(SqlString));
271        }
272    }
273}