Common Mistakes

Chapter 5 - Reading Data using the Dataset Object
byJohn Kauffman, Fabio Claudio Ferracchiatiet al.?
Wrox Press ?2002

If you're having difficulty accessing the individual values within the columns of a table, you might like to use the following checklist to help identify your problem:

• Note that there is no period between the row index and the name of the field: it's Rows(Index) ("FieldName"), not Rows(Index) . ("FieldName").

• The names of the DataTable object and the field both need double quotes and parentheses.

• All of the web server controls you're using (as well as the form, if present) must have the runat="server" attribute set.

• Don't forget that the indexes of all collections - including the collection of items in a ListBox, and the collection of DataRow objects in a DataTable - are zero-based.

• If you're attempting to retrieve a particular row based on a number returned from (say) a ListBox item, and there are gaps in the sequence of DataValues, then the ListBox. SelectedItem. Index numbers may not correspond to the correct row in the data source.