Quote Originally Posted by tg
a dataset can contain zero or more datatables...
No Sir, Dataset contains 1 DataTableCollection, which in turns contains zero or more Datatables, and so on.

That's why you have to specify the index of DataTable when accessing a table inside DataSet.

example.
Code:
DataSet ds = new DataSet();
string item;
item = ds.Tables["tablename"].Rows[rowindex][columnindex].ToString();