Introduction
This is a working C# .NET program that demonstrates how to integrate most of
the features of the DataGrid and DataSet in a single project including select,
insert, update, delete, confirm delete, sort, filter and page. This is a work
in progress and feedback is an important factor in improving this tutorial. Please
report any bugs and I will try to fix them.
A few general concepts are presented here and represent my best understanding
of how the DataSet and DataGrid works.
The SqlDataAdapter provides a bridge between the DataSet and the data source.
Calling Fill, refreshes the data in the DataSet. Calling Update, attempts to
commit any changes in the DataSet. The SqlDataAdapter wizard simplifies building
of data driven forms by automatically generating UPDATE, INSERT and DELETE statements from your SqlDataAdapter SELECT statement. By default, the UPDATE statement implements an Optimistic Concurrency scheme that looks for an unaltered
row on UPDATE.
The DataSet can encapsulate a parent child hierarchy of zero or more data
tables. The DataSet also stores its state, storing both the @original values
and any new uncommitted values. These original values are used to enforce "Optimistic
Concurrency" by searching for unaltered rows on UPDATE. Unlike the DataGrid,
the DataSet does _not_ persist itself on post back.
The DataGrid is used to display data in the HTML page. If DataGrid paging
is not enabled, the DataGrid will display all of the rows in the appropriate
table in the corresponding DataSet. To enable sorting and filtering, the DataGrid
is bound to a View, not to the DataSet.
The View is used to sort and filter data in the DataSet before it is passed
to the DataGrid using the properties:
view.RowFilter
view.Sort
The data path looks like this:
DataBase --> DataSet --> View --> DataGrid