Dynamically assign Select Statement to SqlDataSource

[cyberbless]

I would like to dynamically assign a Select Statment to a a
SqlDataSource. Problem is the SqlDataSource.S elect() Command requires
a "dataSourceSele ctArgument" as one of its arguments.

1. What if I don't have an argument to give to out our the Select
Statement. Or if the arguments are pre-assigned. Take the following
lines of code for example.
---------------------------------------------------------

SqlDataSource.I nsertCommand = "INSERT INTO cart (userID, SID,
itemID, quantity) VALUES ('value1', '"
+ curSessionID
+ "', '"
+ itemID
+"', 1)";
SqlDataSource.S elect();
---------------------------------------------------------
It's part of a standalone class; their is no coordinating .aspx page.
This brings me to my next question: Why does it work as part of the a
..aspx page without an argument? See Below:
---------------------------------------------------------
<asp:SqlDataSou rce
ID="top20_DataS ource"
DataSourceMode= "DataSet"
runat="server"
ProviderName=Sy stem.Data.Odbc
ConnectionStrin g="<%$ ConnectionStrin gs:Conn%>"
SelectCommand=" SELECT itemID, style, title, performers, date,
location, about_item, HTMLimgTag, img_tag_60_x_60 ">
</asp:SqlDataSour ce>
---------------------------------------------------------

Any Answers would be greatly appreciated.