Forms Data Controls :: Select Command In App So Could Execute The Command And Retrive The Data Into A String Variable?

i'm trying to issue a select command in my app soi could execute the command and retrive the data into a string variable.the problem is that this command is overloaded with DataSourceSelectArgument and i can't figure out what it is.i'm using sql server express and when issue a n insert command for example sq.Insert(); i have no problems.this the command that's holding me:

SqlDataSource sq = new SqlDataSource();
sq.ConnectionString = ConfigurationManager.ConnectionStrings["CustomerDatabaseConnectionString1"].ToString();
sq.SelectCommandType = SqlDataSourceCommandType.Text;
sq.SelectCommand = "SELECT * FROM CustomerTable where customerID = 1";
string result = sq.Select(some overload that's stopping me);