/// <summary>
/// Execute a command against a data source, mapping the data reader to an enumerable of record dictionaries.
/// This method perfoms LAZY LOADING/DEFERRED EXECUTION.
/// Note that THE DATA READER WILL NOT BE DISPOSED UPON ENUMERATION OR FOREACH BRANCH OUT.
/// </summary>
/// <param name="dbDataReader"> The target data reader. </param>
/// <param name="recordsAffectedCallback"> Executed when the output count of records affected is available to return (post enumeration). </param>
/// <returns> An enumerable of record dictionary instances, containing key/value pairs of data. </returns>
public IEnumerable <IAdoNetStreamingRecord> GetRecordsFromReader(DbDataReader dbDataReader, Action <int> recordsAffectedCallback)
{
AdoNetStreamingRecord record;
int recordsAffected;
long recordIndex = 0;
string key;
object value;
Guid _ = this.__enter();
if ((object)dbDataReader == null)
{
throw new ArgumentNullException(nameof(dbDataReader));
}
//using (this.__use(_, dbDataReader))
{
this.__trace(_, "before yield loop");
while (dbDataReader.Read())
{
record = new AdoNetStreamingRecord(-1, recordIndex);
for (int fieldIndex = 0; fieldIndex < dbDataReader.FieldCount; fieldIndex++)
{
key = dbDataReader.GetName(fieldIndex);
value = dbDataReader.GetValue(fieldIndex);
value = value.ChangeType <object>();
if (record.ContainsKey(key) || (key ?? string.Empty).Length == 0)
{
key = string.Format("Field_{0:0000}", fieldIndex);
}
record.Add(key, value);
}
this.__trace(_, "on yield item");
recordIndex++;
yield return(record); // LAZY PROCESSING INTENT HERE / DO NOT FORCE EAGER LOAD
}
this.__trace(_, "after yield loop");
//this.__disp(_, dbDataReader);
}
recordsAffected = dbDataReader.RecordsAffected;
if ((object)recordsAffectedCallback != null)
{
recordsAffectedCallback(recordsAffected);
}
this.__leave(_);
}
/// <summary>
/// Execute a command against a data source, mapping the data reader GetSchemaTable() result to an enumerable of record dictionaries.
/// This method perfoms LAZY LOADING/DEFERRED EXECUTION.
/// Note that THE DATA READER WILL NOT BE DISPOSED UPON ENUMERATION OR FOREACH BRANCH OUT.
/// </summary>
/// <param name="dbDataReader"> The target data reader. </param>
/// <param name="recordsAffectedCallback"> Executed when the output count of records affected is available to return (post enumeration). </param>
/// <returns> An enumerable of record dictionary instances, containing key/value pairs of schema metadata. </returns>
public IEnumerable <IAdoNetStreamingRecord> GetSchemaRecordsFromReader(DbDataReader dbDataReader, Action <int> recordsAffectedCallback)
{
ReadOnlyCollection <DbColumn> dbColumns;
DbColumn dbColumn;
PropertyInfo[] propertyInfos;
PropertyInfo propertyInfo;
AdoNetStreamingRecord record;
int recordsAffected;
string key;
object value;
Guid _ = this.__enter();
if ((object)dbDataReader == null)
{
throw new ArgumentNullException(nameof(dbDataReader));
}
if (!dbDataReader.CanGetColumnSchema())
{
throw new NotSupportedException(string.Format("The connection command type '{0}' does not support schema access.", dbDataReader.GetType().FullName));
}
//using (this.__use(_, dbDataReader))
{
dbColumns = dbDataReader.GetColumnSchema();
this.__trace(_, "before yield loop");
if ((object)dbColumns != null)
{
for (long recordIndex = 0; recordIndex < dbColumns.Count; recordIndex++)
{
dbColumn = dbColumns[(int)recordIndex];
propertyInfos = dbColumn.GetType().GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.GetProperty);
record = new AdoNetStreamingRecord(-1, recordIndex);
if ((object)propertyInfos != null)
{
for (int fieldIndex = 0; fieldIndex < propertyInfos.Length; fieldIndex++)
{
propertyInfo = propertyInfos[fieldIndex];
if (propertyInfo.GetIndexParameters().Any())
{
continue;
}
key = propertyInfo.Name;
value = propertyInfo.GetValue(dbColumn);
value = value.ChangeType <object>();
record.Add(key, value);
}
}
this.__trace(_, "on yield item");
yield return(record); // LAZY PROCESSING INTENT HERE / DO NOT FORCE EAGER LOAD
}
}
this.__trace(_, "after yield loop");
//this.__disp(_, dbDataReader);
}
recordsAffected = dbDataReader.RecordsAffected;
if ((object)recordsAffectedCallback != null)
{
recordsAffectedCallback(recordsAffected);
}
this.__leave(_);
}
