/// <summary>
/// Create and prepare an IDbCommand, and call ExecuteReader with the appropriate CommandBehavior.
/// </summary>
/// <remarks>
/// If we created and opened the connection, we want the connection to be closed when the DataReader is closed.
///
/// If the caller provided the connection, we want to leave it to them to manage.
/// </remarks>
/// <param name="connection">A valid IDbConnection, on which to execute this command</param>
/// <param name="transaction">A valid IDbTransaction, or 'null'</param>
/// <param name="commandType">The CommandType (stored procedure, text, etc.)</param>
/// <param name="commandText">The stored procedure name or SQL command</param>
/// <param name="commandParameters">An array of IDataParameters to be associated with the command or 'null' if no parameters are required</param>
/// <param name="connectionOwnership">Indicates whether the connection parameter was provided by the caller, or created by AdoHelper</param>
/// <returns>IDataReader containing the results of the command</returns>
/// <exception cref="System.InvalidOperationException">Thrown if any of the IDataParameters.ParameterNames are null, or if the parameter count does not match the number of values supplied</exception>
/// <exception cref="System.ArgumentNullException">Thrown if commandText is null</exception>
/// <exception cref="System.ArgumentException">Thrown if the parameter count does not match the number of values supplied</exception>
/// <exception cref="System.ArgumentNullException">Thrown if connection is null</exception>
private IDataReader ExecuteReader(IDbConnection connection, IDbTransaction transaction, CommandType commandType, string commandText, IDataParameter[] commandParameters, AdoConnectionOwnership connectionOwnership)
{
if( connection == null ) throw new ArgumentNullException( "connection" );
bool mustCloseConnection = false;
// Create a command and prepare it for execution
IDbCommand cmd = connection.CreateCommand();
try
{
PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters, out mustCloseConnection );
CleanParameterSyntax(cmd);
// override conenctionOwnership if we created the connection in PrepareCommand -- cjbreisch
if (mustCloseConnection)
{
connectionOwnership = AdoConnectionOwnership.Internal;
}
// Create a reader
IDataReader dataReader;
dataReader = ExecuteReader(cmd, connectionOwnership);
ClearCommand( cmd );
return dataReader;
}
catch
{
if( mustCloseConnection )
connection.Close();
throw;
}
}
/// <summary>
/// Execute an IDbCommand (that returns a resultset) against the database specified in
/// the connection string.
/// </summary>
/// <param name="command">The IDbCommand object to use</param>
/// <param name="connectionOwnership">Enum indicating whether the connection was created internally or externally.</param>
/// <returns>A IDataReader containing the resultset generated by the command</returns>
/// <exception cref="System.ArgumentNullException">Thrown if command is null.</exception>
protected virtual IDataReader ExecuteReader(IDbCommand command, AdoConnectionOwnership connectionOwnership)
{
// Clean Up Parameter Syntax
CleanParameterSyntax(command);
if (command.Connection.State != ConnectionState.Open)
{
command.Connection.Open();
connectionOwnership = AdoConnectionOwnership.Internal;
}
// Create a reader
IDataReader dataReader;
// Call ExecuteReader with the appropriate CommandBehavior
if (connectionOwnership == AdoConnectionOwnership.External)
{
dataReader = command.ExecuteReader();
}
else
{
try
{
dataReader = command.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (Exception ex)
{
// Don't just throw ex. It changes the call stack. But we want the ex around for debugging, so...
Debug.WriteLine(ex);
throw;
}
}
ClearCommand( command );
return dataReader;
}
