| The primary purpose of a DataSet is to allow the user to operate on data from a server in a disconnected mode. The temporary separation of data from the server is a desirable thing because it frees memory on the server, as well as connection and network resources. The DataSet allows data to be ‘borrowed’ from the server in relatively small usable chunks. The DataSet then ‘manages’ the connection between the data and allows the user to edit, update, delete, append, or select portions of that data. The DataSet is first and foremost a collection of table objects. These table objects can be imported from various and diverse data sources such as SQL Server, Oracle, XML files, and the like, or they can be entered programmatically or through a convenient User Interface (UI) and then added to the DataSet programmatically. The most useful methods are to Accept Changes, AcceptChanges, RejectChanges, Merge, Clone, a few functions for reading and writing XML and XML schema, and – most important of all- the GetChanges method, which gets a DataSet which contains all of the data changes made to the current one since it was loaded. The table objects look like tables in a regular database, though they are virtual tables, which reside only in memory. The table objects have collections of DataColumns, DataRows, Constraints, DataRelations, Property Collections, DataRowView, and a PrimaryKey, which may be a collection of DataColumns. DataTable Class Members Constructors Visibility | Constructor | Parameters | | | | public | DataTable | ( ) | | | | public | DataTable | ( String tableName ) |
Properties February 11, 2008 Visibility | Name | Value Type | Accessibility | | | | | public | CaseSensitive | Boolean | [ Get , Set ] | | | | | public | ChildRelations | DataRelationCollection | [ Get ] | | | | | public | Columns | DataColumnCollection | [ Get ] | | | | | public | Constraints | ConstraintCollection | [ Get ] | | | | | public | Container | IContainer | [ Get ] | | | | | public | DataSet | DataSet | [ Get ] | | | | | public | DefaultView | DataView | [ Get ] | | | | | public | DesignMode | Boolean | [ Get ] | | | | | public | DisplayExpression | String | [ Get , Set ] | | | | | public | ExtendedProperties | PropertyCollection | [ Get ] | | | | | public | HasErrors | Boolean | [ Get ] | | | | | public | Locale | CultureInfo | [ Get , Set ] | | | | | public | MinimumCapacity | Int32 | [ Get , Set ] | | | | | public | Namespace | String | [ Get , Set ] | | | | | public | ParentRelations | DataRelationCollection | [ Get ] | | | | | public | Prefix | String | [ Get , Set ] | | | | public | PrimaryKey | DataColumn | [ Get , Set ] | | | | | public | Rows | DataRowCollection | [ Get ] | | | | | public | Site | ISite | [ Get , Set ] | | | | | public | TableName | String | [ Get , Set ] |
Methods Visibility | Name | Parameters | Return Type | | | | | public | AcceptChanges | ( ) | Void | | | | | public | BeginInit | ( ) | Void | | | | | public | BeginLoadData | ( ) | Void | | | | | public | Clear | ( ) | Void | | | | | public | Clone | ( ) | DataTable | | | | | public | Compute | ( String expression , String filter ) | Object | | | | | public | Copy | ( ) | DataTable | | | | | public | EndInit | ( ) | Void | | | | | public | EndLoadData | ( ) | Void | | | | | public | GetChanges | ( DataRowState rowStates ) | DataTable | | | | | public | GetChanges | ( ) | DataTable | | | | | public | GetErrors | ( ) | DataRow | | | | | public | ImportRow | ( DataRow row ) | Void | | | | | public | LoadDataRow | ( Object values , Boolean fAcceptChanges ) | DataRow | | | | | public | NewRow | ( ) | DataRow | | | | | public | RejectChanges | ( ) | Void | | | | | public | Reset | ( ) | Void | | | | | public | Select | ( String filterExpression , String sort , DataViewRowState recordStates ) | DataRow | | | | | public | Select | ( String filterExpression ) | DataRow | | | | | public | Select | ( ) | DataRow | | | | | public | Select | ( String filterExpression , String sort ) | DataRow | | | | | public | ToString | ( ) | String |
Events Multicast | Name | Type | | | | multicast | ColumnChanged | DataColumnChangeEventHandler | | | | multicast | ColumnChanging | DataColumnChangeEventHandler | | | | multicast | Disposed | EventHandler | | | | multicast | RowChanged | DataRowChangeEventHandler | | | | multicast | RowChanging | DataRowChangeEventHandler | | | | multicast | RowDeleted | DataRowChangeEventHandler | | | | multicast | RowDeleting | DataRowChangeEventHandler | Rows are added programmatically using the DataRows object: Dim dr as DataRow=tblEmployee.NewRow() dr(“dcFirstName”)=”Elmer” dr(“dcLastName”)=”Fudd” tblEmployee.Rows.Add(dr) Resources - Tutorial: ADO.NET Populate a DataSet from a Database
This tutorial discusses populating a DataSet from a Database. - Tutorial: DataSet Vs. DataReader
This is an interesting resource that discusses DataSet and Datareader. |
