利用反射将Datatable、SqlDataReader转换成List模型

1. DataTable转IList

public class DataTableToList<T>whereT :new()

{

///<summary>

///利用反射将Datatable转换成List模型

///</summary>

///<param name="dt"></param>

///<returns></returns>

public static List<T> ConvertToList(DataTabledt)

{

List<T> list =newList<T>();

Typetype =typeof(T);

stringtempName =string.Empty;

foreach(DataRowdrindt.Rows)

{

T t =newT();

PropertyInfo[] propertys =
t.GetType().GetProperties();

foreach(PropertyInfopiinpropertys)

{

tempName = pi.Name;

if(dt.Columns.Contains(tempName))

{

if(!pi.CanWrite)

{

continue;

}

var value = dr[tempName];

if(value !=DBNull.Value)

{

pi.SetValue(t, value,null);

}

}

}

list.Add(t);

}

returnlist;

}

}

2. SqlDataReader转IList

        /// <summary>
        /// 判断SqlDataReader是否存在某列
        /// </summary>
        /// <param name="dr">SqlDataReader</param>
        /// <param name="columnName">列名</param>
        /// <returns></returns>
        private bool readerExists(SqlDataReader dr, string columnName)
        {

            dr.GetSchemaTable().DefaultView.RowFilter = "ColumnName= '" + columnName + "'";

            return (dr.GetSchemaTable().DefaultView.Count > 0);

        }

        ///<summary>
        ///利用反射和泛型将SqlDataReader转换成List模型
        ///</summary>
        ///<param name="sql">查询sql语句</param>
        ///<returns></returns>

        public IList<T> ExecuteToList<T>(string sql) where T : new()

        {
            IList<T> list;

            Type type = typeof (T);

            string tempName = string.Empty;

            using (SqlDataReader reader = ExecuteReader(sql))
            {
                if (reader.HasRows)
                {
                    list = new List<T>();
                    while (reader.Read())
                    {
                        T t = new T();

                        PropertyInfo[] propertys = t.GetType().GetProperties();

                        foreach (PropertyInfo pi in propertys)
                        {
                            tempName = pi.Name;

                            if (readerExists(reader, tempName))
                            {
                                if (!pi.CanWrite)
                                {
                                    continue;
                                }
                                var value = reader[tempName];

                                if (value != DBNull.Value)
                                {
                                    pi.SetValue(t, value, null);
                                }

                            }

                        }

                        list.Add(t);

                    }
                    return list;
                }
            }
            return null;
        }


3、结果集从存储过程获取

  /// <summary>
        /// 处理存储过程
        /// </summary>
        /// <param name="spName">存储过程名</param>
        /// <param name="parameters">参数数组</param>
        /// <returns>sql数据流</returns>
        protected virtual SqlDataReader ExecuteReaderSP(string spName, ArrayList parameters)
        {
            SqlDataReader result = null;
            cmd.CommandText = spName;
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.Parameters.Clear();
            if (parameters != null)
            {
                foreach (SqlParameter param in parameters)
                {
                    cmd.Parameters.Add(param);
                }
            }
            try
            {
                Open();
                result = cmd.ExecuteReader(CommandBehavior.CloseConnection);
            }
            catch (Exception e)
            {
                if (result != null && (!result.IsClosed))
                {
                    result.Close();
                }
                LogHelper.WriteLog("\r\n方法异常【ExecuteReaderSP(string spName, ArrayList parameters)】" + spName, e);
                throw new Exception(e.Message);
            }
            return result;
        }

       ///<summary>
        ///利用反射将SqlDataReader转换成List模型
        ///</summary>
        ///<param name="spName">存储过程名称</param>
        ///<returns></returns>

        public IList<T> ExecuteQueryListSP<T>(string spName, params SqlParameter[] listParams) where T : new()
        {
            IList<T> list;

            Type type = typeof(T);

            string tempName = string.Empty;

            using (SqlDataReader reader = ExecuteReaderSP(spName, new ArrayList(listParams)))
            {
                if (reader.HasRows)
                {
                    list = new List<T>();
                    while (reader.Read())
                    {
                        T t = new T();

                        PropertyInfo[] propertys = t.GetType().GetProperties();

                        foreach (PropertyInfo pi in propertys)
                        {
                            tempName = pi.Name;

                            //for (int intField = 0; intField < reader.FieldCount; intField++)
                            //{//遍历该列名是否存在
                            //}

                            if (readerExists(reader, tempName))
                            {
                                if (!pi.CanWrite)
                                {
                                    continue;
                                }
                                var value = reader[tempName];

                                if (value != DBNull.Value)
                                {
                                    pi.SetValue(t, value, null);
                                }

                            }

                        }

                        list.Add(t);

                    }
                    return list;
                }
            }
            return null;
        }


原文地址:https://www.cnblogs.com/dashi/p/4034651.html