SQLiteHelper类
1 using System;
2 using System.Configuration;
3 using System.Data;
4 using System.Data.SQLite;
5
6 namespace MyBlog.Data
7 {
8
9 /// <summary>
10 /// SQLiteHelper
11 /// </summary>
12 public class SQLiteHelper : System.IDisposable
13 {
14 private SQLiteConnection _SQLiteConn = null;
15 private SQLiteTransaction _SQLiteTrans = null;
16 private bool _IsRunTrans = false;
17 private string _SQLiteConnString = null;
18 private bool _disposed = false;
19 private bool _autocommit = false;
20 #region 构造/析构函数
21 /// <summary>
22 /// 初始化 SQLiteHelper
23
24 /// </summary>
25 public SQLiteHelper()
26 : this(ConfigurationManager.ConnectionStrings["SQLite"].ConnectionString)
27 {
28 }
29 1 /// <summary>
2 /// 初始化 SQLiteHelper
3 /// </summary>
4 /// <param name="connectionstring">数据库连接字符串</param>
5 public SQLiteHelper(string connectionstring)
6 {
7 this._SQLiteConnString = connectionstring;
8 this._SQLiteConn = new SQLiteConnection(this._SQLiteConnString);
9 this._SQLiteConn.Commit += new SQLiteCommitHandler(_SQLiteConn_Commit);
10 this._SQLiteConn.RollBack += new EventHandler(_SQLiteConn_RollBack);
11 }
12
13 /// <summary>
14 /// SQLiteHelper 析构函数
15 /// </summary>
16 ~SQLiteHelper()
17 {
18 this.Dispose(false);
19 }
20
21 #endregion
22 #region 方法
23 /// <summary>
24 /// 打开数据库连接
25 /// </summary>
26 private void Open()
27 {
28 if (this._SQLiteConn.State == ConnectionState.Closed)
29 {
30 this._SQLiteConn.Open();
31 }
32 }
33 /// <summary>
34 /// 关闭数据库连接
35 /// </summary>
36 private void Close()
37 {
38 if (this._SQLiteConn.State != ConnectionState.Closed)
39 {
40 if (this._IsRunTrans && this._autocommit)
41 {
42 this.Commit();
43 }
44 this._SQLiteConn.Close();
45 }
46 }
47 /// <summary>
48 /// 开始数据库事务
49 /// </summary>
50 public void BeginTransaction()
51 {
52 this._SQLiteConn.BeginTransaction();
53 this._IsRunTrans = true;
54 }
55 /// <summary>
56 /// 开始数据库事务
57 /// </summary>
58 /// <param name="isoLevel">事务锁级别</param>
59 public void BeginTransaction(IsolationLevel isoLevel)
60 {
61 this._SQLiteConn.BeginTransaction(isoLevel);
62 this._IsRunTrans = true;
63 }
64 /// <summary>
65 /// 提交当前挂起的事务
66 /// </summary>
67 public void Commit()
68 {
69 if (this._IsRunTrans)
70 {
71 this._SQLiteTrans.Commit();
72 this._IsRunTrans = false;
73 }
74 }
75 /// <summary>
76 /// 回滚当前挂起的事务
77 /// </summary>
78 public void Rollback()
79 {
80 if (this._IsRunTrans)
81 {
82 this._SQLiteTrans.Rollback();
83 this._IsRunTrans = false;
84 }
85 }
86 /// <summary>
87 /// 执行SQL语句
88 /// </summary>
89 /// <param name="command">SQL语句</param>
90 /// <returns>返回受影响行数 [SELECT 不会返回影响行]</returns>
91 public int Execute(string command)
92 {
93 int result = -1;
94 this.Open();
95 using (SQLiteCommand sqlitecmd = new SQLiteCommand(command))
96 {
97 result = sqlitecmd.ExecuteNonQuery();
98 }
99 this.Close();
100 return result;
101 }
102 /// <summary>
103 /// 执行SQL语句
104 /// </summary>
105 /// <param name="command">SQL语句</param>
106 /// <param name="parameter">参数组</param>
107 /// <returns>返回受影响行数 [SELECT 不会返回影响行]</returns>
108 public int Execute(string command, SQLiteParameter[] parameter)
109 {
110 int result = -1;
111 this.Open();
112 using (SQLiteCommand sqlitecmd = new SQLiteCommand(command))
113 {
114 sqlitecmd.Parameters.AddRange(parameter);
115 result = sqlitecmd.ExecuteNonQuery();
116 }
117 this.Close();
118 return result;
119 }
120 /// <summary>
121 /// 执行SQL语句
122 /// </summary>
123 /// <param name="command">SQL语句</param>
124 /// <returns>返回第一行第一列值</returns>
125 public object ExecuteScalar(string command)
126 {
127 object result = null;
128 this.Open();
129 using (SQLiteCommand sqlitecmd = new SQLiteCommand(command))
130 {
131 result = sqlitecmd.ExecuteScalar();
132 }
133 this.Close();
134 return result;
135 }
136 /// <summary>
137 /// 执行SQL语句
138 /// </summary>
139 /// <param name="command">SQL语句</param>
140 /// <param name="parmeter">参数组</param>
141 /// <returns>返回受影响行数 [SELECT 不会返回影响行]</returns>
142 public object ExecuteScalar(string command, SQLiteParameter[] parmeter)
143 {
144 object result = null;
145 this.Open();
146 using (SQLiteCommand sqlitecmd = new SQLiteCommand(command))
147 {
148 sqlitecmd.Parameters.AddRange(parmeter);
149 result = sqlitecmd.ExecuteScalar();
150 }
151 this.Close();
152 return result;
153 }
154 /// <summary>
155 /// 执行SQL语句
156 /// </summary>
157 /// <param name="command">SQL语句</param>
158 /// <returns>返回DataSet数据集</returns>
159 public DataSet GetDs(string command)
160 {
161 return this.GetDs(command, string.Empty);
162 }
163 public DataSet GetDs(string command, string tablename)
164 {
165 DataSet ds = new DataSet();
166 this.Open();
167 using (SQLiteCommand sqlitecmd = new SQLiteCommand(command, this._SQLiteConn))
168 {
169 using (SQLiteDataAdapter sqliteadapter = new SQLiteDataAdapter(sqlitecmd))
170 {
171 if (string.Empty.Equals(tablename))
172 {
173 sqliteadapter.Fill(ds);
174 }
175 else
176 {
177 sqliteadapter.Fill(ds, tablename);
178 }
179 }
180 }
181 this.Close();
182 return ds;
183 }
184
185 public DataSet GetDs(string command, out SQLiteCommand SqlItecmd)
186 {
187 return this.GetDs(command, string.Empty, out SqlItecmd);
188 }
189
190 public DataSet GetDs(string command, string tablename, out SQLiteCommand SqlItecmd)
191 {
192 DataSet ds = new DataSet();
193 this.Open();
194 SQLiteCommand sqlcmd = new SQLiteCommand(command, this._SQLiteConn);
195 using (SQLiteDataAdapter sqladapter = new SQLiteDataAdapter(sqlcmd))
196 {
197 sqladapter.Fill(ds);
198 }
199 SqlItecmd = sqlcmd;
200 this.Close();
201 return ds;
202 }
203
204 public int Update(DataSet ds, ref SQLiteCommand SqlItecmd)
205 {
206 return this.Update(ds, string.Empty, ref SqlItecmd);
207 }
208
209 public int Update(DataSet ds, string tablename, ref SQLiteCommand SqlItecmd)
210 {
211 int result = -1;
212 this.Open();
213 using (SQLiteDataAdapter sqladapter = new SQLiteDataAdapter(SqlItecmd))
214 {
215 using (SQLiteCommandBuilder sqlcommandbuilder = new SQLiteCommandBuilder(sqladapter))
216 {
217 if (string.Empty.Equals(tablename))
218 {
219 result = sqladapter.Update(ds);
220 }
221 else
222 {
223 result = sqladapter.Update(ds, tablename);
224 }
225 }
226 }
227 this.Close();
228 return result;
229 }
230 /// <summary>
231 /// 释放该实例的托管资源
232 /// </summary>
233 public virtual void Dispose()
234 {
235 this.Dispose(true);
236 GC.SuppressFinalize(this);
237 }
238 protected void Dispose(bool disposing)
239 {
240 if (!this._disposed)
241 {
242 if (disposing)
243 {
244 // 定义释放非托管资源
245 }
246 this._disposed = true;
247 }
248 }
249 #endregion
250 #region 属性
251 /// <summary>
252 /// 获取数据库连接字符串
253 /// </summary>
254 public string ConnectionString
255 {
256 get
257 {
258 return this._SQLiteConnString;
259 }
260 }
261 /// <summary>
262 /// 设置是否自动提交事务
263 /// </summary>
264 public bool AutoCommit
265 {
266 get
267 {
268 return this._autocommit;
269 }
270 set
271 {
272 this._autocommit = value;
273 }
274 }
275 #endregion
276 #region 事件
277 void _SQLiteConn_RollBack(object sender, EventArgs e)
278 {
279 this._IsRunTrans = false;
280 }
281 void _SQLiteConn_Commit(object sender, CommitEventArgs e)
282 {
283 this._IsRunTrans = false;
284 }
285 #endregion
286 }
287 }转载于:https://my.oschina.net/weisenz/blog/200646