QueryHelp

  1 //辅助查询 Author:高兵兵

  2 public class QueryHelp

  3 {

  4     #region IList<T> ToList<T>(string cmdText,string connString) where T : new()

  5     /// <summary>

  6     /// 返回一个list

  7     /// </summary>

  8     /// <typeparam name="T">实体模型</typeparam>

  9     /// <param name="cmdText">存储过程名</param>

 10     /// <param name="connString">连接字符串</param>

 11     /// <returns></returns>

 12     public static IList<T> ToList<T>(string cmdText, string connString) where T : new()

 13     {

 14         using (var read = DbHelp.Create().ExecuteDataReader(cmdText, connString))

 15         {

 16             IList<T> list = null;

 17             var type = typeof(T);

 18             if (read.HasRows)

 19             {

 20 

 21                 list = new List<T>();

 22             }

 23             while (read.Read())

 24             {

 25                 T t = new T();

 26                 foreach (PropertyInfo item in type.GetProperties())

 27                 {

 28                     for (int i = 0; i < read.FieldCount; i++)

 29                     {

 30                         //属性名与查询出来的列名比较

 31                         if (item.Name.ToLower() != read.GetName(i).ToLower()) continue;

 32                         var value = read[i];

 33                         if (value != DBNull.Value)

 34                         {

 35                             item.SetValue(t, value, null);

 36                         }

 37                         break;

 38                     }

 39                 }

 40                 //将创建的对象添加到集合中

 41                 list.Add(t);

 42             }

 43             return list;

 44         }

 45     }

 46     #endregion

 47 

 48     #region  IList<T> ToList<T>(string cmdText, List<DbParameter> listpar, string connString) where T : class, new()

 49     /// <summary>

 50     /// 返回一个list

 51     /// </summary>

 52     /// <typeparam name="T">实体模型</typeparam>

 53     /// <param name="cmdText">存储过程名</param>

 54     /// <param name="listpar">参数列表</param>

 55     /// <param name="connString">连接字符串</param>

 56     /// <returns></returns>

 57     public static IList<T> ToList<T>(string cmdText, List<DbParameter> listpar, string connString) where T : class, new()

 58     {

 59         using (var read = DbHelp.Create().ExecuteDataReader(cmdText, listpar, connString))

 60         {

 61             List<T> list = null;

 62             var type = typeof(T);

 63             if (read.HasRows)

 64             {

 65 

 66                 list = new List<T>();

 67             }

 68             while (read.Read())

 69             {

 70                 T t = new T();

 71                 foreach (PropertyInfo item in type.GetProperties())

 72                 {

 73                     for (int i = 0; i < read.FieldCount; i++)

 74                     {

 75                         //属性名与查询出来的列名比较

 76                         if (item.Name.ToLower() != read.GetName(i).ToLower()) continue;

 77                         object value = read[i];

 78                         if (value != DBNull.Value)

 79                         {

 80                             item.SetValue(t, value, null);

 81                         }

 82                         break;

 83                     }

 84                 }

 85                 //将创建的对象添加到集合中

 86                 list.Add(t);

 87             }

 88             return list;

 89         }

 90     }

 91     #endregion

 92 

 93     #region  IList<T> ToListAsPager<T>(string cmdText, List<DbParameter> listpar, string connString) where T : class, new()

 94     /// <summary>

 95     /// 返回一个list

 96     /// </summary>

 97     /// <typeparam name="T">实体模型</typeparam>

 98     /// <param name="cmdText">存储过程名</param>

 99     /// <param name="listpar">参数列表</param>

100     /// <param name="connString">连接字符串</param>

101     /// <returns></returns>

102     public static IList<T> ToListAsPager<T>(string cmdText, List<DbParameter> listpar, string connString) where T : class, new()

103     {

104         listpar[listpar.Count-1].Direction = ParameterDirection.Output;

105         using (var read = DbHelp.Create().ExecuteDataReader(cmdText, listpar, connString))

106         {

107             List<T> list = null;

108             var type = typeof(T);

109             if (read.HasRows)

110             {

111 

112                 list = new List<T>();

113             }

114             while (read.Read())

115             {

116                 T t = new T();

117                 foreach (PropertyInfo item in type.GetProperties())

118                 {

119                     for (int i = 0; i < read.FieldCount; i++)

120                     {

121                         //属性名与查询出来的列名比较

122                         if (item.Name.ToLower() != read.GetName(i).ToLower()) continue;

123                         object value = read[i];

124                         if (value != DBNull.Value)

125                         {

126                             item.SetValue(t, value, null);

127                         }

128                         break;

129                     }

130                 }

131                 //将创建的对象添加到集合中

132                 list.Add(t);

133             }

134             return list;

135         }

136     }

137     #endregion

138 

139     #region T FirstOrDefault<T>(string cmdText, string connString)

140     /// <summary>

141     /// 返回一个实体模型

142     /// </summary>

143     /// <typeparam name="T">实体模型</typeparam>

144     /// <param name="cmdText">存储过程名</param>

145     /// <param name="connString">连接字符串</param>

146     /// <returns></returns>

147     public static T FirstOrDefault<T>(string cmdText, string connString) where T : class,new()

148     {

149         using (var read = DbHelp.Create().ExecuteDataReader(cmdText, connString))

150         {

151 

152             Type type = typeof(T);

153 

154             if (!read.Read()) return null;

155             T t = new T();

156             foreach (PropertyInfo item in type.GetProperties())

157             {

158                 for (int i = 0; i < read.FieldCount; i++)

159                 {

160                     //属性名与查询出来的列名比较

161                     if (item.Name.ToLower() != read.GetName(i).ToLower()) continue;

162                     object value = read[i];

163                     if (value != DBNull.Value)

164                     {

165                         item.SetValue(t, value, null);

166                     }

167                     break;

168                 }

169 

170             }

171             return t;

172         }

173     }

174     #endregion

175 

176     #region T FirstOrDefault<T>(string cmdText, List<DbParameter> list, string connString)

177     /// <summary>

178     /// 返回一个实体

179     /// </summary>

180     /// <typeparam name="T">实体模型</typeparam>

181     /// <param name="cmdText">存储过程名称</param>

182     /// <param name="ob">object[]</param>

183     /// <param name="connString">连接字符串</param>

184     /// <returns></returns>

185     public static T FirstOrDefault<T>(string cmdText, List<DbParameter> list, string connString) where T : class,new()

186     {

187         using (var read = DbHelp.Create().ExecuteDataReader(cmdText, list, connString))

188         {

189             var type = typeof(T);

190             if (!read.Read()) return null;

191             var t = new T();

192             foreach (var item in type.GetProperties())

193             {

194                 for (var i = 0; i < read.FieldCount; i++)

195                 {

196                     //属性名与查询出来的列名比较

197                     if (item.Name.ToLower() != read.GetName(i).ToLower()) continue;

198                     var value = read[i];

199                     if (value != DBNull.Value)

200                     {

201                         item.SetValue(t, value, null);

202                     }

203                     break;

204                 }

205             }

206             return t;

207         }

208     }

209     #endregion

210 

211 }

QueryHelp