C# DbDataReader.Dispose方法代码示例

        public static List<object> GetColumnFromDataReader(DbDataReader dr, string columnName)
        {
            List<object> column = new List<object>();

            try
            {
                while (dr.Read())
                {
                    column.Add(dr[columnName]);
                }
            }
            finally
            {
                if (dr != null && !dr.IsClosed)
                {
                    dr.Close();  // Data Reader is done (read only, forward only)
                    dr.Dispose();
                }
            }

            return column;
        }

        /// <summary>
        /// Closes the current connection and disposes of the reader passed in
        /// </summary>
        /// <param name="reader">The reader object to dispose of (if there is one, else pass 'null')</param>
        public void CleanUp(DbDataReader reader)
        {
            if (_connection != null && _connection.State == ConnectionState.Open && _transaction == null)
                _connection.Close();

            if (reader != null)
            {
                if (!reader.IsClosed)
                    reader.Close();

                reader.Dispose();
            }
        }

 /// <summary>
 /// Disposes the reader.
 /// </summary>
 /// <param name="reader"></param>
 protected void SafeDispose(DbDataReader reader)
 {
     if (reader != null)
     {
         reader.Dispose();
     }
 }

        public static DataTable JoinData(DbDataReader dr1, DbDataReader dr2, KeyValuePair<string, string> relation)
        {
            // Create the DataTables
            DataTable dt1 = new DataTable("Table1");
            DataTable dt2 = new DataTable("Table2");
            dt1.Load(dr1);
            dt2.Load(dr2);

            dr1.Close();
            dr1.Dispose();
            dr2.Close();
            dr2.Dispose();

            return JoinData(dt1, dt2, relation);
        }

        /// <summary>
        /// Converts a DbDataReader object with one row to a dictionary.
        /// Dict Keys are DbDataReader Columns and Values is the Row.
        /// Will throw if there is more or less than one result.
        /// Note that DbDataReader is read only / forward only, so at then end, the reader object is closed and disposed.
        /// </summary>
        /// <param name="dr"></param>
        /// <returns></returns>
        public static Dictionary<string, object> GetDictFromDataReader(DbDataReader dr)
        {
            Dictionary<string, object> dict = new Dictionary<string, object>();

            try
            {
                if (!dr.HasRows)
                {
                    throw new Exception("DataReader has no rows. Needs to have one.");
                }

                dr.Read();
                for (int i = 0; i < dr.FieldCount; i++)
                {
                    dict.Add(dr.GetName(i), dr[i]);
                }

                if (dr.Read())
                {
                    throw new Exception("DataReader has more than one row. Needs to have only one.");
                }
            }
            finally
            {
                if (dr != null  && !dr.IsClosed)
                {
                    dr.Close();  // DataReader is done (read only, forward only)
                    dr.Dispose();
                }
            }

            return dict;
        }