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DataReader 转换成实体(或List)

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/// <summary>
/// DataReader转换为obj list
/// </summary>
/// <typeparam name="T">泛型</typeparam>
/// <param name="rdr">datareader</param>
/// <returns>返回泛型类型</returns>
protected static IList<T> DataReader2Obj<T>(SqlDataReader rdr)
{
     IList<T> list = new List<T>();

     while (rdr.Read())
     {
          T t = System.Activator.CreateInstance<T>();
          Type obj = t.GetType();
          // 循环字段
          for (int i = 0; i < rdr.FieldCount; i++)
          {
               object tempValue = null;

               if (rdr.IsDBNull(i))
               {

                    string typeFullName = obj.GetProperty(rdr.GetName(i)).PropertyType.FullName;
                    tempValue = GetDBNullValue(typeFullName);

               }
               else
               {
                    tempValue = rdr.GetValue(i);

               }
                 
               obj.GetProperty(rdr.GetName(i)).SetValue(t,tempValue, null);

          }

          list.Add(t);

      }
            return list;
}

        /// <summary>
        /// DataReader转换为obj
        /// </summary>
        /// <typeparam name="T">泛型</typeparam>
        /// <param name="rdr">datareader</param>
        /// <returns>返回泛型类型</returns>
        protected static object DataReaderToObj<T>(SqlDataReader rdr)
        {
            T t = System.Activator.CreateInstance<T>();
            Type obj = t.GetType();

            if (rdr.Read())
            {
                // 循环字段
                for (int i = 0; i < rdr.FieldCount; i++)
                {
                    object tempValue = null;

                    if (rdr.IsDBNull(i))
                    {

                        string typeFullName = obj.GetProperty(rdr.GetName(i)).PropertyType.FullName;
                        tempValue = GetDBNullValue(typeFullName);

                    }
                    else
                    {
                        tempValue = rdr.GetValue(i);

                    }

                    obj.GetProperty(rdr.GetName(i)).SetValue(t, tempValue, null);

                }
                return t;
            }
            else
                return null;
            
        }


        /// <summary>
        /// 返回值为DBnull的默认值
        /// </summary>
        /// <param name="typeFullName">数据类型的全称,类如:system.int32</param>
        /// <returns>返回的默认值</returns>
        private static object GetDBNullValue(string typeFullName)
        {
       
            typeFullName = typeFullName.ToLower();

            if (typeFullName == DataType.String)
            {
                return String.Empty;
            }
            if (typeFullName == DataType.Int32)
            {
                return 0;
            }
            if (typeFullName == DataType.DateTime)
            {
                return Convert.ToDateTime(BaseSet.DateTimeLongNull);
            }
            if (typeFullName == DataType.Boolean)
            {
                return false;
            }
            if (typeFullName == DataType.Int)
            {
                return 0;
            }

            return null;
        }

#region = 返回集合使用例句  =

IList<MeetingsInfo> meetingInfoList = new List<MeetingsInfo>();

using (SqlDataReader rdr = SQLPlus.ExecuteReader(CommandType.Text, strSQL, parms))

{
   meetingInfoList = DataReader2Obj<MeetingsInfo>(rdr);
}
#endregion

#region = 返回实体例句  =
MeetingsInfo meetingInfo = null;
using (SqlDataReader rdr = SQLPlus.ExecuteReader(CommandType.Text, strSQL, parms))
{
     meetingInfo =(MeetingsInfo)DataReaderToObj<MeetingsInfo>(rdr);
}
#endregion

#region = 省略了类似如下内容  =
UsersInfo usersInfo = null;
using (SqlDataReader rdr = SQLPlus.ExecuteReader(CommandType.Text, strSQL, parms))
{
      if (rdr.Read())
      {
           usersInfo = new UsersInfo();
           usersInfo.UserID = rdr.IsDBNull(0) ? 0 : rdr.GetInt32(0);
           usersInfo.UserName = rdr.IsDBNull(1) ? string.Empty : rdr.GetString(1);
           usersInfo.Email = rdr.IsDBNull(2) ? string.Empty : rdr.GetString(2);
           usersInfo.Mobile = rdr.IsDBNull(3) ? string.Empty : rdr.GetString(3);
           usersInfo.RealName = rdr.IsDBNull(4) ? string.Empty : rdr.GetString(4);
           usersInfo.CreateTime = rdr.IsDBNull(5) ? Convert.ToDateTime("0001-1-1 0:00:00") : rdr.GetDateTime(5);
           usersInfo.LastLoginTime = rdr.IsDBNull(6) ? Convert.ToDateTime("0001-1-1 0:00:00") : rdr.GetDateTime(6);
           usersInfo.LastUpdateTime = rdr.IsDBNull(7) ? Convert.ToDateTime("0001-1-1 0:00:00") : rdr.GetDateTime(7);
                }

            }
#endregion
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