C#操作SQLite数据库增、删、改、查 欢迎转载
转载记得留下链接地址哦!!!
最近项目上要使用SQLite数据库,不怕大伙笑话毕业四年多了,一直使用Oracle或者MySQL或者SQLServer,但是真的是没有用过SQLite数据库,据说非常轻量级,但是真没有用过,于是网上大概搜索下,例子比较多,但是么有一个完整的,即使有,也五花八门。。看的人头晕,可能对于他们大神来讲这都太简单了,算求了更新一篇,新来的小伙伴请看下文,大神你就直接飘过吧!本例子运行效果 正式开始吧
1.SQLite的下载安装
自然官网下载对应版本即可,我这里下载的是 Precompiled Binaries for 32-bit Windows (.NET Framework 4.0) 不愿意下载的 可以直接使用我下载过的 点击这里下载
2.减压找出我们所需要的库文件 这里我们只需要俩个文件下图所示
3.下载一个数据库管理系统来创建数据库
我是用的是SQLiteStudio3.1.1版本 自己下载吧 下载地址:https://sqlitestudio.pl/index.rvt?act=download
4.创建数据库以及表
这里创建一个简单的表 UserInfo 完了代码中会有这个数据库 在Debug\bin目录下SQLite数据库文件就一个后缀为.db的文件,就没了。。 通过SQLiteStudio打开该数据库
5.开始使用大伙所熟悉的VS了创建相关类
userinfo的Mode类 1 /// <summary> 2 /// UserInfo:实体类(属性说明自动提取数据库字段的描述信息) 3 /// </summary> 4 [Serializable] 5 public partial class UserInfo 6 { 7 public UserInfo() 8 { } 9 #region Model 10 private int _id; 11 private string _username; 12 private string _pwd; 13 private int? _age; 14 /// <summary> 15 /// 16 /// </summary> 17 public int ID 18 { 19 set { _id = value; } 20 get { return _id; } 21 } 22 /// <summary> 23 /// 24 /// </summary> 25 public string UserName 26 { 27 set { _username = value; } 28 get { return _username; } 29 } 30 /// <summary> 31 /// 32 /// </summary> 33 public string Pwd 34 { 35 set { _pwd = value; } 36 get { return _pwd; } 37 } 38 /// <summary> 39 /// 40 /// </summary> 41 public int? Age 42 { 43 set { _age = value; } 44 get { return _age; } 45 } 46 #endregion Model 47 48 }
UserInfo 的Dal类
1 /// <summary> 2 /// 数据访问类:UserInfo 3 /// </summary> 4 public partial class UserInfo 5 { 6 public UserInfo() 7 { } 8 #region BasicMethod 9 10 /// <summary> 11 /// 得到最大ID 12 /// </summary> 13 public int GetMaxId() 14 { 15 return DbHelperSQLite.GetMaxID("ID", "UserInfo"); 16 } 17 18 /// <summary> 19 /// 是否存在该记录 20 /// </summary> 21 public bool Exists(int ID) 22 { 23 StringBuilder strSql = new StringBuilder(); 24 strSql.Append("select count(1) from UserInfo"); 25 strSql.Append(" where ID=@ID "); 26 SQLiteParameter[] parameters = { 27 new SQLiteParameter("@ID", DbType.Int32,8) }; 28 parameters[0].Value = ID; 29 30 return DbHelperSQLite.Exists(strSql.ToString(), parameters); 31 } 32 33 34 /// <summary> 35 /// 增加一条数据 36 /// </summary> 37 public bool Add(Model.UserInfo model) 38 { 39 StringBuilder strSql = new StringBuilder(); 40 strSql.Append("insert into UserInfo("); 41 strSql.Append("UserName,Pwd,Age)"); 42 strSql.Append(" values ("); 43 strSql.Append("@UserName,@Pwd,@Age)"); 44 SQLiteParameter[] parameters = { 45 new SQLiteParameter("@UserName", DbType.String,50), 46 new SQLiteParameter("@Pwd", DbType.String,25), 47 new SQLiteParameter("@Age", DbType.Int32,8)}; 48 parameters[0].Value = model.UserName; 49 parameters[1].Value = model.Pwd; 50 parameters[2].Value = model.Age; 51 52 int rows = DbHelperSQLite.ExecuteSql(strSql.ToString(), parameters); 53 if (rows > 0) 54 { 55 return true; 56 } 57 else 58 { 59 return false; 60 } 61 } 62 /// <summary> 63 /// 更新一条数据 64 /// </summary> 65 public bool Update(Model.UserInfo model) 66 { 67 StringBuilder strSql = new StringBuilder(); 68 strSql.Append("update UserInfo set "); 69 strSql.Append("UserName=@UserName,"); 70 strSql.Append("Pwd=@Pwd,"); 71 strSql.Append("Age=@Age"); 72 strSql.Append(" where ID=@ID "); 73 SQLiteParameter[] parameters = { 74 new SQLiteParameter("@UserName", DbType.String,50), 75 new SQLiteParameter("@Pwd", DbType.String,25), 76 new SQLiteParameter("@Age", DbType.Int32,8), 77 new SQLiteParameter("@ID", DbType.Int32,8)}; 78 parameters[0].Value = model.UserName; 79 parameters[1].Value = model.Pwd; 80 parameters[2].Value = model.Age; 81 parameters[3].Value = model.ID; 82 83 int rows = DbHelperSQLite.ExecuteSql(strSql.ToString(), parameters); 84 if (rows > 0) 85 { 86 return true; 87 } 88 else 89 { 90 return false; 91 } 92 } 93 94 /// <summary> 95 /// 删除一条数据 96 /// </summary> 97 public bool Delete(int ID) 98 { 99 100 StringBuilder strSql = new StringBuilder(); 101 strSql.Append("delete from UserInfo "); 102 strSql.Append(" where ID=@ID "); 103 SQLiteParameter[] parameters = { 104 new SQLiteParameter("@ID", DbType.Int32,8) }; 105 parameters[0].Value = ID; 106 107 int rows = DbHelperSQLite.ExecuteSql(strSql.ToString(), parameters); 108 if (rows > 0) 109 { 110 return true; 111 } 112 else 113 { 114 return false; 115 } 116 } 117 /// <summary> 118 /// 批量删除数据 119 /// </summary> 120 public bool DeleteList(string IDlist) 121 { 122 StringBuilder strSql = new StringBuilder(); 123 strSql.Append("delete from UserInfo "); 124 strSql.Append(" where ID in (" IDlist ") "); 125 int rows = DbHelperSQLite.ExecuteSql(strSql.ToString()); 126 if (rows > 0) 127 { 128 return true; 129 } 130 else 131 { 132 return false; 133 } 134 } 135 136 137 /// <summary> 138 /// 得到一个对象实体 139 /// </summary> 140 public Model.UserInfo GetModel(int ID) 141 { 142 143 StringBuilder strSql = new StringBuilder(); 144 strSql.Append("select ID,UserName,Pwd,Age from UserInfo "); 145 strSql.Append(" where ID=@ID "); 146 SQLiteParameter[] parameters = { 147 new SQLiteParameter("@ID", DbType.Int32,8) }; 148 parameters[0].Value = ID; 149 150 Model.UserInfo model = new Model.UserInfo(); 151 DataSet ds = DbHelperSQLite.Query(strSql.ToString(), parameters); 152 if (ds.Tables[0].Rows.Count > 0) 153 { 154 return DataRowToModel(ds.Tables[0].Rows[0]); 155 } 156 else 157 { 158 return null; 159 } 160 } 161 162 163 /// <summary> 164 /// 得到一个对象实体 165 /// </summary> 166 public Model.UserInfo DataRowToModel(DataRow row) 167 { 168 Model.UserInfo model = new Model.UserInfo(); 169 if (row != null) 170 { 171 if (row["ID"] != null && row["ID"].ToString() != "") 172 { 173 model.ID = int.Parse(row["ID"].ToString()); 174 } 175 if (row["UserName"] != null) 176 { 177 model.UserName = row["UserName"].ToString(); 178 } 179 if (row["Pwd"] != null) 180 { 181 model.Pwd = row["Pwd"].ToString(); 182 } 183 if (row["Age"] != null && row["Age"].ToString() != "") 184 { 185 model.Age = int.Parse(row["Age"].ToString()); 186 } 187 } 188 return model; 189 } 190 191 /// <summary> 192 /// 获得数据列表 193 /// </summary> 194 public DataSet GetList(string strWhere) 195 { 196 StringBuilder strSql = new StringBuilder(); 197 strSql.Append("select ID,UserName,Pwd,Age "); 198 strSql.Append(" FROM UserInfo "); 199 if (strWhere.Trim() != "") 200 { 201 strSql.Append(" where " strWhere); 202 } 203 return DbHelperSQLite.Query(strSql.ToString()); 204 } 205 206 /// <summary> 207 /// 获取记录总数 208 /// </summary> 209 public int GetRecordCount(string strWhere) 210 { 211 StringBuilder strSql = new StringBuilder(); 212 strSql.Append("select count(1) FROM UserInfo "); 213 if (strWhere.Trim() != "") 214 { 215 strSql.Append(" where " strWhere); 216 } 217 object obj = DbHelperSQLite.GetSingle(strSql.ToString()); 218 if (obj == null) 219 { 220 return 0; 221 } 222 else 223 { 224 return Convert.ToInt32(obj); 225 } 226 } 227 /// <summary> 228 /// 分页获取数据列表 229 /// </summary> 230 public DataSet GetListByPage(string strWhere, string orderby, int startIndex, int endIndex) 231 { 232 StringBuilder strSql = new StringBuilder(); 233 strSql.Append("SELECT * FROM ( "); 234 strSql.Append(" SELECT ROW_NUMBER() OVER ("); 235 if (!string.IsNullOrEmpty(orderby.Trim())) 236 { 237 strSql.Append("order by T." orderby); 238 } 239 else 240 { 241 strSql.Append("order by T.ID desc"); 242 } 243 strSql.Append(")AS Row, T.* from UserInfo T "); 244 if (!string.IsNullOrEmpty(strWhere.Trim())) 245 { 246 strSql.Append(" WHERE " strWhere); 247 } 248 strSql.Append(" ) TT"); 249 strSql.AppendFormat(" WHERE TT.Row between {0} and {1}", startIndex, endIndex); 250 return DbHelperSQLite.Query(strSql.ToString()); 251 } 252 253 #endregion BasicMethod 254 }
Userinfo的BLL类
1 public partial class UserInfo 2 { 3 private readonly DAL.UserInfo dal = new DAL.UserInfo(); 4 public UserInfo() 5 { } 6 #region BasicMethod 7 8 /// <summary> 9 /// 得到最大ID 10 /// </summary> 11 public int GetMaxId() 12 { 13 return dal.GetMaxId(); 14 } 15 16 /// <summary> 17 /// 是否存在该记录 18 /// </summary> 19 public bool Exists(int ID) 20 { 21 return dal.Exists(ID); 22 } 23 24 /// <summary> 25 /// 增加一条数据 26 /// </summary> 27 public bool Add(Model.UserInfo model) 28 { 29 return dal.Add(model); 30 } 31 32 /// <summary> 33 /// 更新一条数据 34 /// </summary> 35 public bool Update(Model.UserInfo model) 36 { 37 return dal.Update(model); 38 } 39 40 /// <summary> 41 /// 删除一条数据 42 /// </summary> 43 public bool Delete(int ID) 44 { 45 46 return dal.Delete(ID); 47 } 48 /// <summary> 49 /// 删除一条数据 50 /// </summary> 51 public bool DeleteList(string IDlist) 52 { 53 return dal.DeleteList(IDlist); 54 } 55 56 /// <summary> 57 /// 得到一个对象实体 58 /// </summary> 59 public Model.UserInfo GetModel(int ID) 60 { 61 62 return dal.GetModel(ID); 63 } 64 65 ///// <summary> 66 ///// 得到一个对象实体,从缓存中 67 ///// </summary> 68 //public Model.UserInfo GetModelByCache(int ID) 69 //{ 70 71 // string CacheKey = "UserInfoModel-" ID; 72 // object objModel = Common.DataCache.GetCache(CacheKey); 73 // if (objModel == null) 74 // { 75 // try 76 // { 77 // objModel = dal.GetModel(ID); 78 // if (objModel != null) 79 // { 80 // int ModelCache = Maticsoft.Common.ConfigHelper.GetConfigInt("ModelCache"); 81 // Maticsoft.Common.DataCache.SetCache(CacheKey, objModel, DateTime.Now.AddMinutes(ModelCache), TimeSpan.Zero); 82 // } 83 // } 84 // catch { } 85 // } 86 // return (Maticsoft.Model.UserInfo)objModel; 87 //} 88 89 /// <summary> 90 /// 获得数据列表 91 /// </summary> 92 public DataSet GetList(string strWhere) 93 { 94 return dal.GetList(strWhere); 95 } 96 /// <summary> 97 /// 获得数据列表 98 /// </summary> 99 public List<Model.UserInfo> GetModelList(string strWhere) 100 { 101 DataSet ds = dal.GetList(strWhere); 102 return DataTableToList(ds.Tables[0]); 103 } 104 /// <summary> 105 /// 获得数据列表 106 /// </summary> 107 public List<Model.UserInfo> DataTableToList(DataTable dt) 108 { 109 List<Model.UserInfo> modelList = new List<Model.UserInfo>(); 110 int rowsCount = dt.Rows.Count; 111 if (rowsCount > 0) 112 { 113 Model.UserInfo model; 114 for (int n = 0; n < rowsCount; n ) 115 { 116 model = dal.DataRowToModel(dt.Rows[n]); 117 if (model != null) 118 { 119 modelList.Add(model); 120 } 121 } 122 } 123 return modelList; 124 } 125 126 /// <summary> 127 /// 获得数据列表 128 /// </summary> 129 public DataSet GetAllList() 130 { 131 return GetList(""); 132 } 133 134 /// <summary> 135 /// 分页获取数据列表 136 /// </summary> 137 public int GetRecordCount(string strWhere) 138 { 139 return dal.GetRecordCount(strWhere); 140 } 141 /// <summary> 142 /// 分页获取数据列表 143 /// </summary> 144 public DataSet GetListByPage(string strWhere, string orderby, int startIndex, int endIndex) 145 { 146 return dal.GetListByPage(strWhere, orderby, startIndex, endIndex); 147 } 148 /// <summary> 149 /// 分页获取数据列表 150 /// </summary> 151 //public DataSet GetList(int PageSize,int PageIndex,string strWhere) 152 //{ 153 //return dal.GetList(PageSize,PageIndex,strWhere); 154 //} 155 156 #endregion BasicMethod 157 #region ExtensionMethod 158 159 #endregion ExtensionMethod 160 }
创建SQLite帮助类
1 /// <summary> 2 /// 数据访问基础类(基于SQLite) 3 /// 可以用户可以修改满足自己项目的需要。 4 /// </summary> 5 public abstract class DbHelperSQLite 6 { 7 //数据库连接字符串(web.config来配置),可以动态更改connectionString支持多数据库. 8 public static string connectionString = CreateConnectionString(); 9 public DbHelperSQLite() 10 { 11 } 12 private static string CreateConnectionString() 13 { 14 15 string dbName = ConfigurationManager.AppSettings["SQLiteDB"]; 16 string sqlLitePath = "data source=" System.Environment.CurrentDirectory "\\" dbName ";version=3;"; 17 return sqlLitePath; 18 } 19 20 #region 公用方法 21 22 public static int GetMaxID(string FieldName, string TableName) 23 { 24 string strsql = "select max(" FieldName ") 1 from " TableName; 25 object obj = GetSingle(strsql); 26 if (obj == null) 27 { 28 return 1; 29 } 30 else 31 { 32 return int.Parse(obj.ToString()); 33 } 34 } 35 public static bool Exists(string strSql) 36 { 37 object obj = GetSingle(strSql); 38 int cmdresult; 39 if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) 40 { 41 cmdresult = 0; 42 } 43 else 44 { 45 cmdresult = int.Parse(obj.ToString()); 46 } 47 if (cmdresult == 0) 48 { 49 return false; 50 } 51 else 52 { 53 return true; 54 } 55 } 56 public static bool Exists(string strSql, params SQLiteParameter[] cmdParms) 57 { 58 object obj = GetSingle(strSql, cmdParms); 59 int cmdresult; 60 if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) 61 { 62 cmdresult = 0; 63 } 64 else 65 { 66 cmdresult = int.Parse(obj.ToString()); 67 } 68 if (cmdresult == 0) 69 { 70 return false; 71 } 72 else 73 { 74 return true; 75 } 76 } 77 78 #endregion 79 80 #region 执行简单SQL语句 81 82 /// <summary> 83 /// 执行SQL语句,返回影响的记录数 84 /// </summary> 85 /// <param name="SQLString">SQL语句</param> 86 /// <returns>影响的记录数</returns> 87 public static int ExecuteSql(string SQLString) 88 { 89 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 90 { 91 using (SQLiteCommand cmd = new SQLiteCommand(SQLString, connection)) 92 { 93 try 94 { 95 connection.Open(); 96 int rows = cmd.ExecuteNonQuery(); 97 return rows; 98 } 99 catch (System.Data.SQLite.SQLiteException E) 100 { 101 connection.Close(); 102 throw new Exception(E.Message); 103 } 104 } 105 } 106 } 107 108 /// <summary> 109 /// 执行多条SQL语句,实现数据库事务。 110 /// </summary> 111 /// <param name="SQLStringList">多条SQL语句</param> 112 public static void ExecuteSqlTran(ArrayList SQLStringList) 113 { 114 using (SQLiteConnection conn = new SQLiteConnection(connectionString)) 115 { 116 conn.Open(); 117 SQLiteCommand cmd = new SQLiteCommand(); 118 cmd.Connection = conn; 119 SQLiteTransaction tx = conn.BeginTransaction(); 120 cmd.Transaction = tx; 121 try 122 { 123 for (int n = 0; n < SQLStringList.Count; n ) 124 { 125 string strsql = SQLStringList[n].ToString(); 126 if (strsql.Trim().Length > 1) 127 { 128 cmd.CommandText = strsql; 129 cmd.ExecuteNonQuery(); 130 } 131 } 132 tx.Commit(); 133 } 134 catch (System.Data.SQLite.SQLiteException E) 135 { 136 tx.Rollback(); 137 throw new Exception(E.Message); 138 } 139 } 140 } 141 /// <summary> 142 /// 执行带一个存储过程参数的的SQL语句。 143 /// </summary> 144 /// <param name="SQLString">SQL语句</param> 145 /// <param name="content">参数内容,比如一个字段是格式复杂的文章,有特殊符号,可以通过这个方式添加</param> 146 /// <returns>影响的记录数</returns> 147 public static int ExecuteSql(string SQLString, string content) 148 { 149 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 150 { 151 SQLiteCommand cmd = new SQLiteCommand(SQLString, connection); 152 SQLiteParameter myParameter = new SQLiteParameter("@content", DbType.String); 153 myParameter.Value = content; 154 cmd.Parameters.Add(myParameter); 155 try 156 { 157 connection.Open(); 158 int rows = cmd.ExecuteNonQuery(); 159 return rows; 160 } 161 catch (System.Data.SQLite.SQLiteException E) 162 { 163 throw new Exception(E.Message); 164 } 165 finally 166 { 167 cmd.Dispose(); 168 connection.Close(); 169 } 170 } 171 } 172 /// <summary> 173 /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例) 174 /// </summary> 175 /// <param name="strSQL">SQL语句</param> 176 /// <param name="fs">图像字节,数据库的字段类型为image的情况</param> 177 /// <returns>影响的记录数</returns> 178 public static int ExecuteSqlInsertImg(string strSQL, byte[] fs) 179 { 180 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 181 { 182 SQLiteCommand cmd = new SQLiteCommand(strSQL, connection); 183 SQLiteParameter myParameter = new SQLiteParameter("@fs", DbType.Binary); 184 myParameter.Value = fs; 185 cmd.Parameters.Add(myParameter); 186 try 187 { 188 connection.Open(); 189 int rows = cmd.ExecuteNonQuery(); 190 return rows; 191 } 192 catch (System.Data.SQLite.SQLiteException E) 193 { 194 throw new Exception(E.Message); 195 } 196 finally 197 { 198 cmd.Dispose(); 199 connection.Close(); 200 } 201 } 202 } 203 204 /// <summary> 205 /// 执行一条计算查询结果语句,返回查询结果(object)。 206 /// </summary> 207 /// <param name="SQLString">计算查询结果语句</param> 208 /// <returns>查询结果(object)</returns> 209 public static object GetSingle(string SQLString) 210 { 211 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 212 { 213 using (SQLiteCommand cmd = new SQLiteCommand(SQLString, connection)) 214 { 215 try 216 { 217 connection.Open(); 218 object obj = cmd.ExecuteScalar(); 219 if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) 220 { 221 return null; 222 } 223 else 224 { 225 return obj; 226 } 227 } 228 catch (System.Data.SQLite.SQLiteException e) 229 { 230 connection.Close(); 231 throw new Exception(e.Message); 232 } 233 } 234 } 235 } 236 /// <summary> 237 /// 执行查询语句,返回SQLiteDataReader 238 /// </summary> 239 /// <param name="strSQL">查询语句</param> 240 /// <returns>SQLiteDataReader</returns> 241 public static SQLiteDataReader ExecuteReader(string strSQL) 242 { 243 SQLiteConnection connection = new SQLiteConnection(connectionString); 244 SQLiteCommand cmd = new SQLiteCommand(strSQL, connection); 245 try 246 { 247 connection.Open(); 248 SQLiteDataReader myReader = cmd.ExecuteReader(); 249 return myReader; 250 } 251 catch (System.Data.SQLite.SQLiteException e) 252 { 253 throw new Exception(e.Message); 254 } 255 256 } 257 /// <summary> 258 /// 执行查询语句,返回DataSet 259 /// </summary> 260 /// <param name="SQLString">查询语句</param> 261 /// <returns>DataSet</returns> 262 public static DataSet Query(string SQLString) 263 { 264 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 265 { 266 DataSet ds = new DataSet(); 267 try 268 { 269 connection.Open(); 270 SQLiteDataAdapter command = new SQLiteDataAdapter(SQLString, connection); 271 command.Fill(ds, "ds"); 272 } 273 catch (System.Data.SQLite.SQLiteException ex) 274 { 275 throw new Exception(ex.Message); 276 } 277 return ds; 278 } 279 } 280 281 282 #endregion 283 284 #region 执行带参数的SQL语句 285 286 /// <summary> 287 /// 执行SQL语句,返回影响的记录数 288 /// </summary> 289 /// <param name="SQLString">SQL语句</param> 290 /// <returns>影响的记录数</returns> 291 public static int ExecuteSql(string SQLString, params SQLiteParameter[] cmdParms) 292 { 293 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 294 { 295 using (SQLiteCommand cmd = new SQLiteCommand()) 296 { 297 try 298 { 299 PrepareCommand(cmd, connection, null, SQLString, cmdParms); 300 int rows = cmd.ExecuteNonQuery(); 301 cmd.Parameters.Clear(); 302 return rows; 303 } 304 catch (System.Data.SQLite.SQLiteException E) 305 { 306 throw new Exception(E.Message); 307 } 308 } 309 } 310 } 311 312 313 /// <summary> 314 /// 执行多条SQL语句,实现数据库事务。 315 /// </summary> 316 /// <param name="SQLStringList">SQL语句的哈希表(key为sql语句,value是该语句的SQLiteParameter[])</param> 317 public static void ExecuteSqlTran(Hashtable SQLStringList) 318 { 319 using (SQLiteConnection conn = new SQLiteConnection(connectionString)) 320 { 321 conn.Open(); 322 using (SQLiteTransaction trans = conn.BeginTransaction()) 323 { 324 SQLiteCommand cmd = new SQLiteCommand(); 325 try 326 { 327 //循环 328 foreach (DictionaryEntry myDE in SQLStringList) 329 { 330 string cmdText = myDE.Key.ToString(); 331 SQLiteParameter[] cmdParms = (SQLiteParameter[])myDE.Value; 332 PrepareCommand(cmd, conn, trans, cmdText, cmdParms); 333 int val = cmd.ExecuteNonQuery(); 334 cmd.Parameters.Clear(); 335 336 trans.Commit(); 337 } 338 } 339 catch 340 { 341 trans.Rollback(); 342 throw; 343 } 344 } 345 } 346 } 347 348 349 /// <summary> 350 /// 执行一条计算查询结果语句,返回查询结果(object)。 351 /// </summary> 352 /// <param name="SQLString">计算查询结果语句</param> 353 /// <returns>查询结果(object)</returns> 354 public static object GetSingle(string SQLString, params SQLiteParameter[] cmdParms) 355 { 356 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 357 { 358 using (SQLiteCommand cmd = new SQLiteCommand()) 359 { 360 try 361 { 362 PrepareCommand(cmd, connection, null, SQLString, cmdParms); 363 object obj = cmd.ExecuteScalar(); 364 cmd.Parameters.Clear(); 365 if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) 366 { 367 return null; 368 } 369 else 370 { 371 return obj; 372 } 373 } 374 catch (System.Data.SQLite.SQLiteException e) 375 { 376 throw new Exception(e.Message); 377 } 378 } 379 } 380 } 381 382 /// <summary> 383 /// 执行查询语句,返回SQLiteDataReader 384 /// </summary> 385 /// <param name="strSQL">查询语句</param> 386 /// <returns>SQLiteDataReader</returns> 387 public static SQLiteDataReader ExecuteReader(string SQLString, params SQLiteParameter[] cmdParms) 388 { 389 SQLiteConnection connection = new SQLiteConnection(connectionString); 390 SQLiteCommand cmd = new SQLiteCommand(); 391 try 392 { 393 PrepareCommand(cmd, connection, null, SQLString, cmdParms); 394 SQLiteDataReader myReader = cmd.ExecuteReader(); 395 cmd.Parameters.Clear(); 396 return myReader; 397 } 398 catch (System.Data.SQLite.SQLiteException e) 399 { 400 throw new Exception(e.Message); 401 } 402 403 } 404 405 /// <summary> 406 /// 执行查询语句,返回DataSet 407 /// </summary> 408 /// <param name="SQLString">查询语句</param> 409 /// <returns>DataSet</returns> 410 public static DataSet Query(string SQLString, params SQLiteParameter[] cmdParms) 411 { 412 using (SQLiteConnection connection = new SQLiteConnection(connectionString)) 413 { 414 SQLiteCommand cmd = new SQLiteCommand(); 415 PrepareCommand(cmd, connection, null, SQLString, cmdParms); 416 using (SQLiteDataAdapter da = new SQLiteDataAdapter(cmd)) 417 { 418 DataSet ds = new DataSet(); 419 try 420 { 421 da.Fill(ds, "ds"); 422 cmd.Parameters.Clear(); 423 } 424 catch (System.Data.SQLite.SQLiteException ex) 425 { 426 throw new Exception(ex.Message); 427 } 428 return ds; 429 } 430 } 431 } 432 433 434 private static void PrepareCommand(SQLiteCommand cmd, SQLiteConnection conn, SQLiteTransaction trans, string cmdText, SQLiteParameter[] cmdParms) 435 { 436 if (conn.State != ConnectionState.Open) 437 conn.Open(); 438 cmd.Connection = conn; 439 cmd.CommandText = cmdText; 440 if (trans != null) 441 cmd.Transaction = trans; 442 cmd.CommandType = CommandType.Text;//cmdType; 443 if (cmdParms != null) 444 { 445 foreach (SQLiteParameter parm in cmdParms) 446 cmd.Parameters.Add(parm); 447 } 448 } 449 450 #endregion 451 452 453 454 }
6.创建一个WinForm窗体用于测试
大概是这样的,我用的是VS2017 数据库配置文件新增App.config文件 其余的没有用,是Mysql的连接字符串,可以不用管。。。
窗体代码大概是这样的比较简单,只是实现简单的操作,具体细节那就交个大家了。。。
1 public partial class Form1 : Form 2 { 3 public Form1() 4 { 5 InitializeComponent(); 6 } 7 8 9 BLL.UserInfo bll = new BLL.UserInfo(); 10 11 12 //数据库连接 13 SQLiteConnection m_dbConnection; 14 private void button1_Click(object sender, EventArgs e) 15 { 16 17 DataSet ds = bll.GetAllList(); 18 19 this.dataGridView1.DataSource = ds.Tables[0]; 20 21 } 22 23 int count = 0; 24 private void button2_Click(object sender, EventArgs e) 25 { 26 count ; 27 Model.UserInfo userInfo = new Model.UserInfo(); 28 userInfo.UserName = "Count" count; 29 userInfo.Pwd = "123456"; 30 userInfo.Age = count; 31 32 bll.Add(userInfo); 33 34 DataSet ds = bll.GetAllList(); 35 this.dataGridView1.DataSource = ds.Tables[0]; 36 37 } 38 39 private void button3_Click(object sender, EventArgs e) 40 { 41 42 Model.UserInfo userInfo = new Model.UserInfo(); 43 userInfo.ID = int.Parse(this.label1.Text); 44 userInfo.UserName = this.textBox1.Text; 45 userInfo.Pwd = this.textBox2.Text; 46 userInfo.Age = int.Parse(this.textBox3.Text); 47 bll.Update(userInfo); 48 49 50 DataSet ds = bll.GetAllList(); 51 this.dataGridView1.DataSource = ds.Tables[0]; 52 53 54 } 55 56 private void dataGridView1_MouseClick(object sender, MouseEventArgs e) 57 { 58 DataGridViewRow row = this.dataGridView1.CurrentRow; 59 this.label1.Text = row.Cells[0].Value.ToString(); 60 this.textBox1.Text = row.Cells[1].Value.ToString(); 61 this.textBox2.Text = row.Cells[2].Value.ToString(); 62 this.textBox3.Text = row.Cells[3].Value.ToString(); 63 64 65 } 66 67 private void button4_Click(object sender, EventArgs e) 68 { 69 bll.Delete(int.Parse(this.label1.Text)); 70 71 72 DataSet ds = bll.GetAllList(); 73 this.dataGridView1.DataSource = ds.Tables[0]; 74 } 75 76 private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e) 77 { 78 79 Process.Start("IExplore", "https://www.cnblogs.com/JiYF/"); 80 } 81 }
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