自己动手写ORM（02）：Sql生成器实现
回顾：
上一节中鄙人通过解析表达式树生成Sql碎片，其中我也把解析表达式类代码贴了出来，文章发布之后我对ExpressionAnalyzer类做了些改动，下面我还会将代码贴出来，废话不多说，直接进入今天的主题。
实体类设计：
首先，我觉得要想直接通过实体类生成Sql语句，那么你可能要知道这个实体类对应数据库表中的主键和外键是什么，在此我加入了两个特性来标识主键和外键关系。如下
/// <summary>
/// 外键表特性（导航属性）
/// </summary>
public class GuidanceAttribute : System.Attribute
{
/// <summary>
/// 依赖字段
/// </summary>
public string DepandField { get; set; }
}
public class MessageAttribute : System.Attribute
{
/// <summary>
/// 链接字符串名
/// </summary>
public string ConStr { get; set; }
}
public class PrimaryKeyAttribute : System.Attribute
{
}
实体类如下：
1 using LC.Model; 2 using LC.Model.Attribute; 3 using System; 4 using System.Collections.Generic; 5 using System.Linq; 6 using System.Text; 7 using System.Threading.Tasks; 8 using LC.Model.Common; 9 using LC.Test; 10 using LC.Test.Model; 11 12 namespace LC.Model 13 { 14 [Message(ConStr = "sql")] 15 public class SYS_User 16 { 17 [PrimaryKey] 18 public string Id { get; set; } 19 public string UserName { get; set; } 20 21 public Guid? RoleId { get; set; } 22 public Guid? CityId { get; set; } 23 [Guidance(DepandField = "RoleId")] 24 public SYS_Role Role { get; set; } 25 26 [Guidance(DepandField = "CityId")] 27 public City City { get; set; } 28 29 public int Gender { get; set; } 30 31 public bool Deleted { get; set; } 32 33 public DateTime CreateTime { get; set; } 34 } 35 }
那么在生成sql的过程中，我需要知道实体所对应表的主键和外键关系，此关系我保存在类TableInfo中：
1 public class TableInfo 2 { 3 public string ConStr { get; set; } 4 public string RName { get; set; } 5 public string TableName { get; set; } 6 public string PrimaryKey { get; set; } 7 public Dictionary<string, TableInfo> ForeignRefs { get; set; } 8 }
具体怎么将实体类转换成TableInfo，在此我暂时使用反射，不过多解释，因为暂时还不知道有什么方法不用反射获取特性。
有了TableInfo，我们就可以轻松的生成Sql了。
查询命令生成器设计：
下面上图，这是我用画图工具话的，不要问我为什么，因为电脑没有建模工具。。。
直接上代码：
1 public interface ICreator 2 { 3 SqlDebris Debris { get; set; } 4 } 5 6 public class BaseCreator : ICreator 7 { 8 public SqlDebris Debris { get; set; } 9 public BaseCreator() 10 { 11 Debris = new SqlDebris(); 12 } 13 } 14 public interface IQuery : ICreator 15 { 16 void CreateFrom(AnalysisTable data, TableInfo tableInfo); 17 void CreateSelect(AnalysisData data); 18 void CreateWhere(AnalysisData data); 19 void AppendOrder(AnalysisData data, OrderTypeEnum orderType); 20 void AppendSkip(int count); 21 void AppendTake(int count); 22 void GetCount(); 23 }
下面是QueryCreator的实现：
1 public class QueryCreator : BaseCreator, IQuery 2 { 3 public virtual void CreateSelect(AnalysisData data) 4 { 5 var primaryTable = data.Table; 6 StringBuilder sb = new StringBuilder(); 7 //默认查询全部列 8 if (data.StackList.Count <= 0) 9 { 10 sb.AppendFormat("[{0}].*", primaryTable.RName); 11 } 12 else 13 { 14 //查询部分列 15 for (int i = 0; i < data.StackList.Count; i += 3) 16 { 17 sb.AppendFormat("{0} {1} {2},", data.StackList[i], data.StackList[i + 1], data.StackList[i + 2]); 18 } 19 sb.Remove(sb.Length - 1, 1); 20 } 21 Debris.Select = sb.ToString(); 22 } 23 public virtual void CreateFrom(AnalysisTable anlyTable, TableInfo tableInfo) 24 { 25 if (null == anlyTable) 26 { 27 throw new BusinessException(BusinessRes.TableCanNotBeEmpty); 28 } 29 //默认排序信息 30 if (string.IsNullOrEmpty(Debris.Order)) 31 { 32 Debris.Order = string.Format("[{0}].{1} {2}", anlyTable.RName, tableInfo.PrimaryKey, System.Enum.GetName(typeof(OrderTypeEnum), OrderTypeEnum.ASC)); 33 } 34 StringBuilder sb = new StringBuilder(); 35 sb.AppendFormat("[{0}] AS [{1}]", anlyTable.Name, anlyTable.RName); 36 AppendLeftJoinTables(anlyTable, tableInfo, sb); 37 Debris.From = sb.ToString(); 38 } 39 public virtual void CreateWhere(AnalysisData data) 40 { 41 if (data == null || data.StackList.Count() <= 0) 42 { 43 return; 44 } 45 Debris.Where = string.Join(" ", data.StackList); 46 } 47 public virtual void AppendSkip(int count) 48 { 49 Debris.Skip = count; 50 } 51 public virtual void AppendTake(int count) 52 { 53 Debris.Take = count; 54 } 55 public virtual void AppendOrder(AnalysisData data, OrderTypeEnum orderType) 56 { 57 if (data.StackList.Count <= 0) 58 { 59 return; 60 } 61 var field = data.StackList.First(); 62 StringBuilder sb = new StringBuilder(Debris.Order); 63 if (string.IsNullOrEmpty(Debris.Order)) 64 { 65 sb.AppendFormat("{0} {1}", field, System.Enum.GetName(typeof(OrderTypeEnum), orderType)); 66 Debris.Order = sb.ToString(); 67 return; 68 } 69 sb.AppendFormat(",{0} {1}", field, System.Enum.GetName(typeof(OrderTypeEnum), orderType)); 70 Debris.Order = sb.ToString(); 71 } 72 public void GetCount() 73 { 74 Debris.Select = "COUNT(1)"; 75 } 76 77 private KeyValuePair<string, TableInfo> GetForeignReference(TableInfo tInfo, string rName) 78 { 79 var keyValue = tInfo.ForeignRefs.Where(u => u.Value.RName == rName).FirstOrDefault(); 80 if (string.IsNullOrEmpty(keyValue.Key)) 81 { 82 foreach (var item in tInfo.ForeignRefs) 83 { 84 var foreignTable = GetForeignReference(item.Value, rName); 85 if (!string.IsNullOrEmpty(keyValue.Key)) 86 { 87 return foreignTable; 88 } 89 } 90 91 } 92 93 return keyValue; 94 } 95 private void AppendLeftJoinTables(AnalysisTable anlyTable, TableInfo tableInfo, StringBuilder sb) 96 { 97 ///添加关系表信息 98 foreach (var item in anlyTable.leftJoins) 99 { 100 var _foreignRef = GetForeignReference(tableInfo, item.RName); 101 if (string.IsNullOrEmpty(_foreignRef.Key)) 102 { 103 throw new BusinessException(BusinessRes.WhitoutThisForeignReference); 104 } 105 sb.AppendFormat(" LEFT JOIN [{0}] AS [{1}] ON [{1}].{2}=[{3}].{4} ", item.Name, item.RName, _foreignRef.Value.PrimaryKey, anlyTable.RName, _foreignRef.Key); 106 AppendLeftJoinTables(item, _foreignRef.Value, sb); 107 } 108 } 109 }
到此为止，生成的Sql依然是不完整的Sql碎片，我们需要将碎片合并成Sql语句，我写了一个工具类如下：
保存碎片类：
1 public class SqlDebris 2 { 3 public string Where { get; set; } 4 #region 查询 5 public string From { get; set; } 6 public string Select { get; set; } 7 public string Order { get; set; } 8 public int Skip { get; set; } 9 public int? Take { get; set; } 10 #endregion 11 #region 修改 12 public string Set { get; set; } 13 public string Update { get; set; } 14 #endregion 15 #region 新增 16 17 public string InsertTable { get; set; } 18 public string Columns { get; set; } 19 public string Values { get; set; } 20 21 #endregion 22 }
通过下面工具类生成完整Sql语句：
1 public class CommandTextHelper 2 { 3 public static string GetSelectCommandText(ICreator creator) 4 { 5 var debris = creator.Debris; 6 StringBuilder sb = new StringBuilder(); 7 if (debris.Take == null) 8 { 9 sb.Append(" SELECT * FROM ("); 10 } 11 else 12 { 13 //分页 14 sb.AppendFormat(" SELECT TOP {0} * FROM (", debris.Take); 15 } 16 sb.AppendFormat("SELECT {0},ROW_NUMBER() OVER(ORDER BY {2} ) as ROWNUMBER FROM {1}", debris.Select, debris.From, debris.Order); 17 //条件 18 if (!string.IsNullOrEmpty(debris.Where)) 19 { 20 sb.AppendFormat(" WHERE {0} ", debris.Where); 21 } 22 sb.Append(") as NEW_TABLE "); 23 sb.AppendFormat(" WHERE ROWNUMBER>{0}", debris.Skip); 24 return sb.ToString(); 25 } 26 27 public static string GetCountCommandText(ICreator creator) 28 { 29 var debris = creator.Debris; 30 StringBuilder sb = new StringBuilder(); 31 32 sb.AppendFormat("SELECT {0} FROM {1}", debris.Select, debris.From); 33 //条件 34 if (!string.IsNullOrEmpty(debris.Where)) 35 { 36 sb.AppendFormat(" WHERE {0} ", debris.Where); 37 } 38 return sb.ToString(); 39 } 40 41 public static string GetUpdateCommandText(ICreator creator) 42 { 43 var debris = creator.Debris; 44 StringBuilder sb = new StringBuilder(); 45 sb.AppendFormat("UPDATE {0} ", debris.Update); 46 sb.AppendFormat("SET {0} ", debris.Set); 47 sb.AppendFormat("WHERE {0}", debris.Where); 48 return sb.ToString(); 49 } 50 public static string GetInsertCommandText(ICreator creator) 51 { 52 var debris = creator.Debris; 53 StringBuilder sb = new StringBuilder(); 54 sb.AppendFormat("INSERT INTO {0}", debris.InsertTable); 55 sb.AppendFormat("({0}) ", debris.Columns); 56 sb.AppendFormat("VALUES({0})", debris.Values); 57 return sb.ToString(); 58 } 59 public static string GetDeleteCommandText(ICreator creator) 60 { 61 var debris = creator.Debris; 62 StringBuilder sb = new StringBuilder(); 63 sb.AppendFormat("DELETE FROM {0}", debris.From); 64 sb.AppendFormat(" WHERE {0}", debris.Where); 65 return sb.ToString(); 66 } 67 }
下面是CommandFactory<TEntity>:
1 public class CommandFactory<TEntity> 2 { 3 protected TableInfo _tableInfo; 4 public CommandFactory() 5 { 6 _tableInfo = new Mapper().MapToTable(typeof(TEntity)); 7 } 8 }
下面是QueryCommand<TEntity>实现:
1 public class QueryCommand<TEntity> : CommandFactory<TEntity> 2 { 3 //sql碎片生成器 4 private IQuery _creator; 5 //查询参数 6 private Dictionary<string, object> _params; 7 8 private AnalysisTable _table; 9 10 public QueryCommand() 11 { 12 _creator = new QueryCreator(); 13 } 14 public QueryCommand<TEntity> Where(Expression<Func<TEntity, bool>> exp) 15 { 16 var retData = new ExpressionAnalyzer(exp).GetAnalysisResult(); 17 _creator.CreateWhere(retData); 18 _params = retData.ParamList; 19 _table = retData.Table; 20 return this; 21 } 22 public QueryCommand<TEntity> OrderBy(Expression<Func<TEntity, object>> exp) 23 { 24 _creator.AppendOrder(new ExpressionAnalyzer(exp).GetAnalysisResult(), OrderTypeEnum.ASC); 25 return this; 26 } 27 public QueryCommand<TEntity> OrderByDescding(Expression<Func<TEntity, object>> exp) 28 { 29 _creator.AppendOrder(new ExpressionAnalyzer(exp).GetAnalysisResult(), OrderTypeEnum.DESC); 30 return this; 31 } 32 public QueryCommand<TEntity> ThenBy(Expression<Func<TEntity, object>> exp) 33 { 34 return OrderBy(exp); 35 } 36 public QueryCommand<TEntity> ThenByDescding(Expression<Func<TEntity, object>> exp) 37 { 38 return OrderByDescding(exp); 39 } 40 public QueryCommand<TEntity> Skip(int count) 41 { 42 _creator.AppendSkip(count); 43 return this; 44 } 45 public QueryCommand<TEntity> Take(int count) 46 { 47 _creator.AppendTake(count); 48 return this; 49 } 50 public Command<TResult> GetSelectCommand<TResult>(Expression<Func<TEntity, TResult>> exp) 51 { 52 var _result = new ExpressionAnalyzer(exp, _table).GetAnalysisResult(); 53 _creator.CreateSelect(_result); 54 _creator.CreateFrom(_result.Table, _tableInfo); 55 return new Command<TResult>() 56 { 57 ConStr = _tableInfo.ConStr, 58 CommandText = CommandTextHelper.GetSelectCommandText(_creator), 59 Params = _params 60 }; 61 } 62 public Command<int> GetCountCommand(Expression<Func<TEntity, bool>> exp) 63 { 64 var retData = new ExpressionAnalyzer(exp).GetAnalysisResult(); 65 _creator.CreateWhere(retData); 66 _creator.GetCount(); 67 _creator.CreateFrom(retData.Table, _tableInfo); 68 return new Command<int>() 69 { 70 CommandText = CommandTextHelper.GetCountCommandText(_creator), 71 ConStr = _tableInfo.ConStr, 72 Params = retData.ParamList 73 }; 74 } 75 }
下面是测试结果仅供参考：
1 [TestMethod] 2 public void TestQueryCommand() 3 { 4 var param = new SYS_User() 5 { 6 UserName = "lichun", 7 RoleId = Guid.NewGuid() 8 }; 9 QueryCommand<SYS_User> f = new QueryCommand<SYS_User>(); 10 var command = f.Where(u => u.City.Name == "cengdu" && u.Role.Config.Name.Contains(param.UserName)).GetSelectCommand(u => new 11 { 12 u.Id, 13 u.Role.Name 14 }); 15 ShowCommand(command); 16 } 17 18 19 public void ShowCommand<TResult>(Command<TResult> command) 20 { 21 Console.WriteLine("链接字符串："); 22 Console.WriteLine(command.ConStr); 23 Console.WriteLine("----------------------------------");
Console.WriteLine("Sql命令："); 24 Console.WriteLine(command.CommandText); 25 26 Console.WriteLine("----------------------------------"); 27 if (command.Params != null) 28 {
Console.WriteLine("参数："); 29 foreach (var item in command.Params) 30 { 31 32 Console.WriteLine("{0} → {1}", item.Key, item.Value); 33 } 34 } 35 36 }
测试结果如下：
修改的ExpressionAnalyzer如下：
1 public class ExpressionAnalyzer 2 { 3 /// <summary> 4 /// 表达式所有参数集合 5 /// </summary> 6 private Dictionary<string, object> _params; 7 /// <summary> 8 /// 命名参数别名 9 /// </summary> 10 private const string _argName = "TAB"; 11 /// <summary> 12 /// 解析结果 13 /// </summary> 14 private AnalysisData _resultData; 15 16 public ExpressionAnalyzer() 17 { 18 _resultData = new AnalysisData(); 19 _params = new Dictionary<string, object>(); 20 } 21 public ExpressionAnalyzer(LambdaExpression exp, AnalysisTable table = null) 22 : this() 23 { 24 if (table != null) 25 { 26 _resultData.Table = table; 27 } 28 29 if (exp != null) 30 { 31 AppendParams(GetChildValue(exp.Body), _params); 32 foreach (var item in exp.Parameters) 33 { 34 AnalysisTables(item); 35 } 36 AnalysisExpression(exp.Body, true); 37 } 38 } 39 40 41 42 public AnalysisData GetAnalysisResult() 43 { 44 return _resultData; 45 } 46 47 48 /// <summary> 49 /// 解析表达式 50 /// </summary> 51 /// <param name="exp"></param> 52 /// <param name="isLeftChild"></param> 53 private void AnalysisExpression(Expression exp, bool isLeftChild = true) 54 { 55 switch (exp.NodeType) 56 { 57 case ExpressionType.AndAlso: 58 _resultData.StackList.Add("("); 59 AnalysisExpression(GetChildExpression(exp)); 60 _resultData.StackList.Add(")"); 61 _resultData.StackList.Add("AND"); 62 _resultData.StackList.Add("("); 63 AnalysisExpression(GetChildExpression(exp, false), false); 64 _resultData.StackList.Add(")"); 65 break; 66 case ExpressionType.OrElse: 67 _resultData.StackList.Add("("); 68 AnalysisExpression(GetChildExpression(exp)); 69 _resultData.StackList.Add(")"); 70 _resultData.StackList.Add("OR"); 71 _resultData.StackList.Add("("); 72 AnalysisExpression(GetChildExpression(exp, false), false); 73 _resultData.StackList.Add(")"); 74 break; 75 case ExpressionType.Equal: 76 AnalysisExpression(GetChildExpression(exp)); 77 _resultData.StackList.Add("="); 78 AnalysisExpression(GetChildExpression(exp, false), false); 79 break; 80 case ExpressionType.NotEqual: 81 AnalysisExpression(GetChildExpression(exp)); 82 _resultData.StackList.Add("!="); 83 AnalysisExpression(GetChildExpression(exp, false), false); 84 break; 85 case ExpressionType.GreaterThanOrEqual: 86 AnalysisExpression(GetChildExpression(exp)); 87 _resultData.StackList.Add(">="); 88 AnalysisExpression(GetChildExpression(exp, false), false); 89 break; 90 case ExpressionType.GreaterThan: 91 AnalysisExpression(GetChildExpression(exp)); 92 _resultData.StackList.Add(">"); 93 AnalysisExpression(GetChildExpression(exp, false), false); 94 break; 95 case ExpressionType.LessThan: 96 AnalysisExpression(GetChildExpression(exp)); 97 _resultData.StackList.Add("<"); 98 AnalysisExpression(GetChildExpression(exp, false), false); 99 break; 100 case ExpressionType.LessThanOrEqual: 101 AnalysisExpression(GetChildExpression(exp)); 102 _resultData.StackList.Add("<="); 103 AnalysisExpression(GetChildExpression(exp, false), false); 104 break; 105 case ExpressionType.Call: 106 var imExp = exp as MethodCallExpression; 107 AnalysisExpression(imExp.Object, true); 108 _resultData.StackList.Add("LIKE"); 109 if (imExp.Arguments.Count > 0) 110 { 111 var arg0 = imExp.Arguments[0] as MemberExpression; 112 _resultData.StackList.Add("'%'+"); 113 AnalysisExpression(imExp.Arguments[0], false); 114 _resultData.StackList.Add("+'%'"); 115 } 116 break; 117 case ExpressionType.MemberAccess: 118 if (isLeftChild) 119 { 120 AnalysisTables(exp); 121 var mberExp = exp as MemberExpression; 122 var parentName = GetExpressionName(mberExp.Expression); 123 if (!string.IsNullOrEmpty(parentName)) 124 { 125 _resultData.StackList.Add(string.Format("[{0}].{1}", parentName, GetExpressionName(exp))); 126 break; 127 } 128 _resultData.StackList.Add(GetExpressionName(exp)); 129 } 130 else 131 { 132 var paramName = GetParamName(exp); 133 _resultData.ParamList.Add(paramName, _params[paramName]); 134 _resultData.StackList.Add(paramName); 135 } 136 break; 137 case ExpressionType.Constant: 138 var constent = exp as ConstantExpression; 139 if (constent.Value == null) 140 { 141 var op = _resultData.StackList.ElementAt(_resultData.StackList.Count - 1); 142 _resultData.StackList.RemoveAt(_resultData.StackList.Count - 1); 143 if (string.Equals(op, "=")) 144 { 145 _resultData.StackList.Add("IS NULL"); 146 } 147 else 148 { 149 _resultData.StackList.Add("IS NOT NULL"); 150 } 151 break; 152 } 153 if (constent.Value.GetType() == typeof(String)) 154 { 155 _resultData.StackList.Add(string.Format("'{0}'", constent.Value)); 156 break; 157 } 158 if (constent.Value.GetType() == typeof(bool)) 159 { 160 if (_resultData.StackList.Count > 0) 161 { 162 var value = Convert.ToBoolean(constent.Value); 163 _resultData.StackList.Add(string.Format("{0}", value ? "1" : "0")); 164 } 165 166 break; 167 } 168 _resultData.StackList.Add(string.Format("{0}", constent.Value)); 169 break; 170 case ExpressionType.Convert: 171 var uExp = exp as UnaryExpression; 172 AnalysisExpression(uExp.Operand, isLeftChild); 173 break; 174 case ExpressionType.New: 175 var newExp = exp as NewExpression; 176 //解析查询字段 177 for (int i = 0; i < newExp.Arguments.Count; i++) 178 { 179 AnalysisExpression(newExp.Arguments[i]); 180 _resultData.StackList.Add("AS"); 181 _resultData.StackList.Add(string.Format("'{0}'", newExp.Members[i].Name)); 182 } 183 break; 184 case ExpressionType.Parameter: 185 throw new BusinessException(BusinessRes.SelectObjectMastBeAnNewObject); 186 //AnalysisExpression(Expression.New(exp.Type)); 187 //break; 188 default: 189 break; 190 } 191 192 } 193 /// <summary> 194 /// 获取孩子节点 195 /// </summary> 196 /// <param name="exp"></param> 197 /// <param name="getLeft"></param> 198 /// <returns></returns> 199 private Expression GetChildExpression(Expression exp, bool getLeft = true) 200 { 201 var className = exp.GetType().Name; 202 switch (className) 203 { 204 case "BinaryExpression": 205 case "LogicalBinaryExpression": 206 var bExp = exp as BinaryExpression; 207 return getLeft ? bExp.Left : bExp.Right; 208 case "PropertyExpression": 209 case "FieldExpression": 210 var mberExp = exp as MemberExpression; 211 return mberExp; 212 case "MethodBinaryExpression": 213 var mbExp = exp as BinaryExpression; 214 return getLeft ? mbExp.Left : mbExp.Right; 215 case "UnaryExpression": 216 var unaryExp = exp as UnaryExpression; 217 return unaryExp; 218 case "ConstantExpression": 219 var cExp = exp as ConstantExpression; 220 return cExp; 221 case "InstanceMethodCallExpressionN": 222 var imExp = exp as MethodCallExpression; 223 return imExp; 224 default: 225 return null; 226 } 227 } 228 /// <summary> 229 /// 获取变量名 230 /// </summary> 231 /// <param name="exp"></param> 232 /// <param name="isLeftChild"></param> 233 /// <returns></returns> 234 private string GetExpressionName(Expression exp) 235 { 236 var className = exp.GetType().Name; 237 switch (className) 238 { 239 case "PropertyExpression": 240 case "FieldExpression": 241 var mberExp = exp as MemberExpression; 242 return string.Format("{0}", mberExp.Member.Name); 243 case "TypedParameterExpression": 244 return _argName; 245 default: 246 return string.Empty; 247 } 248 } 249 /// <summary> 250 /// 获取参数名 251 /// </summary> 252 /// <param name="exp"></param> 253 /// <param name="isLeftChild"></param> 254 /// <returns></returns> 255 private string GetParamName(Expression exp) 256 { 257 var className = exp.GetType().Name; 258 switch (className) 259 { 260 case "PropertyExpression": 261 case "FieldExpression": 262 var mberExp = exp as MemberExpression; 263 return string.Format("@{0}", mberExp.Member.Name); 264 case "TypedParameterExpression": 265 var texp = exp as ParameterExpression; 266 return string.Format("@{0}", texp.Name); 267 default: 268 return string.Empty; 269 } 270 } 271 /// <summary> 272 /// 解析表信息 273 /// </summary> 274 /// <param name="exp"></param> 275 /// <param name="refTable">引用表</param> 276 private void AnalysisTables(Expression exp, AnalysisTable refTable = null) 277 { 278 var className = exp.GetType().Name; 279 switch (className) 280 { 281 case "PropertyExpression": 282 case "FieldExpression": 283 var mberExp = exp as MemberExpression; 284 if (IsDefaultType(mberExp.Type)) 285 { 286 AnalysisTables(mberExp.Expression); 287 break; 288 } 289 var _tampTab = GetTableByRName(_resultData.Table, mberExp.Member.Name); 290 if (_tampTab == null) 291 { 292 _tampTab = new AnalysisTable() 293 { 294 RName = mberExp.Member.Name, 295 Name = mberExp.Type.Name, 296 TableType = mberExp.Type 297 298 }; 299 AnalysisTables(mberExp.Expression, _tampTab); 300 } 301 if (refTable != null) 302 { 303 _tampTab.leftJoins.Add(refTable); 304 } 305 break; 306 case "TypedParameterExpression": 307 //命名参数表达式 308 var texp = exp as ParameterExpression; 309 if (!IsDefaultType(texp.Type)) 310 { 311 if (null == _resultData.Table) 312 { 313 _resultData.Table = new AnalysisTable() 314 { 315 RName = _argName, 316 Name = texp.Type.Name, 317 TableType = texp.Type 318 }; 319 } 320 if (refTable != null) 321 { 322 _resultData.Table.leftJoins.Add(refTable); 323 } 324 } 325 break; 326 default: 327 break; 328 } 329 } 330 /// <summary> 331 /// 遍历树，深度优先 332 /// </summary> 333 /// <param name="table"></param> 334 /// <param name="rName"></param> 335 /// <returns></returns> 336 private AnalysisTable GetTableByRName(AnalysisTable table, string rName) 337 { 338 var _tempTable = table; 339 if (_tempTable.RName == rName) 340 { 341 return _tempTable; 342 } 343 foreach (var item in _tempTable.leftJoins) 344 { 345 _tempTable = GetTableByRName(item, rName); 346 if (_tempTable != null) 347 { 348 return _tempTable; 349 } 350 } 351 return null; 352 } 353 /// <summary> 354 /// 解析获取表达式的值 355 /// </summary> 356 /// <param name="exp"></param> 357 /// <param name="leftChild"></param> 358 /// <returns></returns> 359 private object GetChildValue(Expression exp) 360 { 361 var className = exp.GetType().Name; 362 switch (className) 363 { 364 case "BinaryExpression": 365 case "LogicalBinaryExpression": 366 var lExp = exp as BinaryExpression; 367 var ret = GetChildValue(lExp.Left); 368 if (IsNullDefaultType(ret)) 369 { 370 ret = GetChildValue(lExp.Right); 371 } 372 return ret; 373 case "MethodBinaryExpression": 374 var mbExp = exp as BinaryExpression; 375 var ret1 = GetChildValue(mbExp.Left); 376 if (IsNullDefaultType(ret1)) 377 { 378 ret1 = GetChildValue(mbExp.Right); 379 } 380 return ret1; 381 382 case "PropertyExpression": 383 case "FieldExpression": 384 var mberExp = exp as MemberExpression; 385 return GetChildValue(mberExp.Expression); 386 case "ConstantExpression": 387 var cExp = exp as ConstantExpression; 388 return cExp.Value; 389 case "UnaryExpression": 390 var unaryExp = exp as UnaryExpression; 391 return GetChildValue(unaryExp.Operand); 392 case "InstanceMethodCallExpressionN": 393 var imExp = exp as MethodCallExpression; 394 if (imExp.Arguments.Count > 0) 395 { 396 return GetChildValue(imExp.Arguments[0]); 397 } 398 return null; 399 default: 400 return null; 401 } 402 403 } 404 /// <summary> 405 /// 初始化所有参数 406 /// </summary> 407 /// <param name="paramObj"></param> 408 private void AppendParams(object paramObj, Dictionary<string, object> _params) 409 { 410 if (IsNullDefaultType(paramObj)) 411 { 412 return; 413 } 414 if (_params == null) 415 { 416 _params = new Dictionary<string, object>(); 417 } 418 foreach (var item in paramObj.GetType().GetProperties()) 419 { 420 if (IsDefaultType(item.PropertyType)) 421 { 422 var value = item.GetValue(paramObj, null); 423 if (value != null) 424 { 425 _params.Add(string.Format("@{0}", item.Name), value); 426 } 427 continue; 428 } 429 430 AppendParams(item.GetValue(paramObj), _params); 431 } 432 433 foreach (var item in paramObj.GetType().GetFields()) 434 { 435 if (IsDefaultType(item.FieldType)) 436 { 437 var value = item.GetValue(paramObj); 438 if (value != null) 439 { 440 _params.Add(string.Format("@{0}", item.Name), value); 441 } 442 continue; 443 } 444 AppendParams(item.GetValue(paramObj), _params); 445 } 446 } 447 public Dictionary<string, object> GetParams(object paramObj) 448 { 449 Dictionary<string, object> dicParams = new Dictionary<string, object>(); 450 AppendParams(paramObj, dicParams); 451 return dicParams; 452 } 453 /// <summary> 454 /// 判断是否是系统默认基本类型 455 /// </summary> 456 /// <param name="type"></param> 457 /// <returns></returns> 458 private bool IsNullDefaultType(object obj) 459 { 460 if (obj == null) 461 { 462 return true; 463 } 464 return IsDefaultType(obj.GetType()); 465 } 466 private bool IsDefaultType(Type type) 467 { 468 string defaultType = @"String|Boolean|Double|Int32|Int64|Int16|Single|DateTime|Decimal|Char|Object|Guid"; 469 470 Regex e = new Regex(defaultType, RegexOptions.IgnoreCase); 471 if (type.Name.ToLower().Contains("nullable")) 472 { 473 if (type.GenericTypeArguments.Count() > 0) 474 { 475 return e.IsMatch(type.GenericTypeArguments[0].Name); 476 } 477 } 478 return e.IsMatch(type.Name); 479 } 480 }
共同学习共同进步，表达有些乱，希望各位大神多多包涵。
