You can handle the SqlDataSource.Selected, SqlDataSource.Updated, SqlDataSource.Inserted, or SqlDataSource.Deleted event to examine and manipulate the properties of the System.Data.Common.DbCommand after it is submitted by the System.Web.UI.WebControls.SqlDataSource control to the database. The SqlDataSourceStatusEventArgs.Command property enables you to access return values and values in any output parameters after the database operation is performed through its System.Data.Common.DbCommand.Parameters property, as well as the System.Data.Common.DbCommand.CommandText property, which represents the SQL query, command, or stored procedure name that was submitted to the database.

Any output parameters are specifically from parameters that have an System.Data.ParameterDirection.InputOutput or System.Data.ParameterDirection.Output value for the Parameter.Direction property of the System.Web.UI.WebControls.Parameter object. A return value is from a parameter that has a System.Data.ParameterDirection.ReturnValue value.