If the SqlDataSource.SelectCommand property contains a parameterized SQL query, the SqlDataSource.SelectParameters collection contains any System.Web.UI.WebControls.Parameter objects that correspond to the parameter placeholders in the SQL string.

Depending on the ADO.NET provider, the order of the parameters in the SqlDataSource.SelectParameters collection might be important. The System.Data.OleDb and System.Data.Odbc providers associate the parameters in the collection according to the order that the parameters appear in the parameterized SQL query. The System.Data.SqlClient provider, which is the default ADO.NET provider for the System.Web.UI.WebControls.SqlDataSource control, associates the parameters in the collection by matching the name of the parameter with a placeholder alias in the SQL query. For more information about parameterized SQL queries and commands, see Using Parameters with the SqlDataSource Control.

The SqlDataSource.SelectParameters property retrieves the SqlDataSourceView.SelectParameters property that is contained by the System.Web.UI.WebControls.SqlDataSourceView object that is associated with the System.Web.UI.WebControls.SqlDataSource control.