上一篇简单的对轻量级ORM开发开了个头。这篇主要聊下ORM框架的设计思路。
ORM本质上是对数据库操作的抽象。大体上我将其分为对数据结构的抽象和对执行方法的抽象。
我的ORM设计图：
ORM框架需要完成.net数据和数据库中数据的相互转换，以及对SQL语句中经典的增删改查操作的抽象封装。
封装方法代码：
1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5 using System.Data; 6 using System.Data.Common; 7 using Model.Entities; 8 9 namespace DAL.ErpSqlDAL.SqlFactory 10 { 11 /// <summary>CRUD方法抽象 12 /// 创建人：雷旭鹏(leo) 2014-1-13 13 /// 联系方式：leixupeng823@163.com 14 /// </summary> 15 /// <typeparam name="T"></typeparam> 16 public abstract class OperateEntity<T>:ResolveEntity<T> where T :BaseEntity 17 { 18 public OperateEntity(DbCmd dbCmd, string entityName, Type entityType) 19 : base(dbCmd, entityName, entityType) 20 { 21 } 22 23 /// <summary>添加实体 24 /// </summary> 25 /// <param name="entityList">要添加的内容</param> 26 /// <returns></returns> 27 public virtual object AddEntity(IList<T> entityList) 28 { 29 try 30 { 31 base.SourceEntity = entityList; 32 base.ConditionEntity = null; 33 base.OperateType = OperateType.INSERT; 34 base.EntityToSql(); 35 36 string strSql = base.CommandString; 37 38 return DBHelper.ExecuteScalar(dbCmd.Cmd, CommandType.Text, strSql, base.Parameters.ToArray()); 39 } 40 catch (Exception ex) 41 { 42 throw ex; 43 } 44 } 45 /// <summary>修改实体,要修改的内容和条件一一对应 46 /// </summary> 47 /// <param name="entityList">要修改的内容</param> 48 /// <param name="conditionList">条件</param> 49 /// <returns></returns> 50 public virtual int ModEntity(IList<T> entityList, IList<T> conditionList) 51 { 52 try 53 { 54 base.SourceEntity = entityList; 55 base.ConditionEntity = conditionList; 56 base.OperateType = OperateType.UPDATE; 57 58 base.EntityToSql(); 59 string strSql = base.CommandString; 60 return DBHelper.ExecuteNonQuery(dbCmd.Cmd, CommandType.Text, strSql, base.Parameters.ToArray()); 61 } 62 catch 63 { 64 throw; 65 } 66 } 67 /// <summary>根据主键修改实体 68 /// </summary> 69 /// <param name="entityList">要修改的内容和包含主键值的实体</param> 70 /// <returns></returns> 71 public virtual int ModEntity(IList<T> entityList) 72 { 73 try 74 { 75 IList<T> cndEntity = new List<T>(); 76 CreatePKConditionFromSourceEntity(entityList, cndEntity); 77 return ModEntity(entityList, cndEntity); 78 } 79 catch 80 { 81 throw; 82 } 83 } 84 /// <summary>删除实体 85 /// </summary> 86 /// <param name="conditionList">删除的条件</param> 87 /// <returns></returns> 88 public virtual int DelEntity(IList<T> conditionList) 89 { 90 try 91 { 92 base.SourceEntity = conditionList; 93 base.ConditionEntity = conditionList; 94 base.OperateType = OperateType.DELETE; 95 96 base.EntityToSql(); 97 string strSql = base.CommandString; 98 return DBHelper.ExecuteNonQuery(dbCmd.Cmd, CommandType.Text, strSql, base.Parameters.ToArray()); 99 } 100 catch 101 { 102 throw; 103 } 104 } 105 /// <summary>得到实体 106 /// </summary> 107 /// <param name="condition">查询条件</param> 108 /// <returns></returns> 109 public virtual IList<T> GetEntity(T condition) 110 { 111 try 112 { 113 if (condition != null) 114 { 115 IList<T> coditionLists = new List<T>(); 116 coditionLists.Add(condition); 117 118 base.ConditionEntity = coditionLists; 119 base.SourceEntity = coditionLists; 120 } 121 base.OperateType = OperateType.SELECT; 122 123 base.EntityToSql(); 124 string strSql = base.CommandString; 125 return base.DateSetToEntity(DBHelper.GetDataSet(dbCmd.Adapter, dbCmd.Cmd, CommandType.Text, strSql, base.Parameters.ToArray())); 126 } 127 catch 128 { 129 throw; 130 } 131 } 132 /// <summary>得到一个值 133 /// </summary> 134 /// <param name="conditionList">查询条件</param> 135 /// <returns></returns> 136 public virtual Object GetValue(T conditionList) 137 { 138 try 139 { 140 IList<T> coditionLists = new List<T>(); 141 coditionLists.Add(conditionList); 142 143 base.SourceEntity = coditionLists; 144 base.ConditionEntity = coditionLists; 145 base.OperateType = OperateType.SELECT; 146 147 base.EntityToSql(); 148 string strSql = base.CommandString; 149 return DBHelper.ExecuteScalar(dbCmd.Cmd, CommandType.Text, strSql, base.Parameters.ToArray()); 150 } 151 catch 152 { 153 throw; 154 } 155 } 156 157 //exce by sql 158 /// <summary>执行存储过程得到一个值 159 /// </summary> 160 /// <param name="sqlStr">存储过程的名称</param> 161 /// <param name="Parameters">参数</param> 162 /// <returns></returns> 163 protected virtual Object GetValueByProc(string sqlStr, params DbParameter[] Parameters) 164 { 165 try 166 { 167 return DBHelper.ExecuteScalar(dbCmd.Cmd, CommandType.StoredProcedure, sqlStr, Parameters); 168 } 169 catch 170 { 171 throw; 172 } 173 } 174 /// <summary>执行SQL语句得到一个值 175 /// </summary> 176 /// <param name="sqlStr">SQL语句</param> 177 /// <param name="Parameters">参数</param> 178 /// <returns></returns> 179 protected virtual Object GetValueBySql(string sqlStr, params DbParameter[] Parameters) 180 { 181 try 182 { 183 return DBHelper.ExecuteScalar(dbCmd.Cmd, CommandType.Text, sqlStr, Parameters); 184 } 185 catch 186 { 187 throw; 188 } 189 } 190 /// <summary>执行SQL，返回受影响的函数 191 /// </summary> 192 /// <param name="sqlStr">存储过程的名称</param> 193 /// <param name="Parameters">参数</param> 194 /// <returns></returns> 195 protected virtual int ExecuteSql(string sqlStr, params DbParameter[] Parameters) 196 { 197 try 198 { 199 return DBHelper.ExecuteNonQuery(dbCmd.Cmd, CommandType.Text, sqlStr, Parameters); 200 } 201 catch 202 { 203 throw; 204 } 205 } 206 /// <summary>执行存储过程,返回受影响的函数 207 /// </summary> 208 /// <param name="sqlStr">存储过程的名称</param> 209 /// <param name="Parameters">参数</param> 210 /// <returns></returns> 211 protected virtual int ExecuteProc(string sqlStr, params DbParameter[] Parameters) 212 { 213 try 214 { 215 return DBHelper.ExecuteNonQuery(dbCmd.Cmd, CommandType.StoredProcedure, sqlStr, Parameters); 216 } 217 catch 218 { 219 throw; 220 } 221 } 222 223 /// <summary>通过SQL语句得到实体 224 /// </summary> 225 /// <param name="sqlStr">SQL</param> 226 /// <returns></returns> 227 protected virtual IList<T> GetEntityBySql(string sqlStr) 228 { 229 try 230 { 231 return base.DateSetToEntity(DBHelper.GetDataSet(dbCmd.Adapter, dbCmd.Cmd, CommandType.Text, sqlStr, null)); 232 } 233 catch 234 { 235 throw; 236 } 237 } 238 /// <summary>通过SQL语句得到DataSet 239 /// </summary> 240 /// <param name="sqlStr">SQL</param> 241 /// <returns></returns> 242 protected virtual DataSet GetDataSetBySql(string sqlStr) 243 { 244 try 245 { 246 return DBHelper.GetDataSet(dbCmd.Adapter, dbCmd.Cmd, CommandType.Text, sqlStr, null); 247 } 248 catch 249 { 250 throw; 251 } 252 } 253 /// <summary>通过SQL语句得到实体 254 /// </summary> 255 /// <param name="sqlStr">SQL</param> 256 /// <param name="Parameters">参数</param> 257 /// <returns></returns> 258 protected virtual IList<T> GetEntityBySql(string sqlStr, params DbParameter[] Parameters) 259 { 260 try 261 { 262 return base.DateSetToEntity(DBHelper.GetDataSet(dbCmd.Adapter, dbCmd.Cmd, CommandType.Text, sqlStr, Parameters)); 263 } 264 catch 265 { 266 throw; 267 } 268 } 269 /// <summary>通过存储过程，语句得到实体 270 /// </summary> 271 /// <param name="sqlStr">SQL</param> 272 /// <param name="Parameters">参数</param> 273 /// <returns></returns> 274 protected virtual IList<T> GetEntityByProc(string sqlStr, params DbParameter[] Parameters) 275 { 276 try 277 { 278 return base.DateSetToEntity(DBHelper.GetDataSet(dbCmd.Adapter, dbCmd.Cmd, CommandType.StoredProcedure, sqlStr, Parameters)); 279 } 280 catch 281 { 282 throw; 283 } 284 } 285 } 286 }
下一篇将讲下从代码上如何实现上面的设计图。