How can I map the results of a sql query onto objects?

Question

Currently, I am using something like this:

    try
    {
      dr = SQL.Execute(sql);

      if(dr != null) {
         while(dr.Read()) {
           CustomObject         


        

Answer 1

Assumption: if you need objects only for serialization or simple ad-hoc output.

You can use ExpandoObject and SqlDataReader.GetSchemaTable() like this:

    private IEnumerable ReaderToAnonymmous(SqlCommand comm) {
        using (var reader = comm.ExecuteReader()) {
            var schemaTable = reader.GetSchemaTable();

            List colnames = new List();
            foreach (DataRow row in schemaTable.Rows) {
                colnames.Add(row["ColumnName"].ToString());
            }

            while (reader.Read()) {
                var data = new ExpandoObject() as IDictionary;
                foreach (string colname in colnames) {
                    var val = reader[colname];
                    data.Add(colname, Convert.IsDBNull(val) ? null : val);
                }

                yield return (ExpandoObject)data;
            }
        }
    }

Although there are posted faster solutions (i posted this as alternative lazy approach for ad-hoc SQL/Reader results/outputs).