DATAVIEW OBJECT
- The DataView class represents a customized view of DataTable
- The relationship between DataTable and DataView are governed by the rules of a well-known design pattern; the document/view model
- The DataTable ojects act as the document, whereas the DataView behaves as the view
- At any moment there can be multiple views for the same underlying data
- The view is implemented by maintaining a separate array with the indexes of the original rows that match the criteria set on the view
- By default, the table view is unfiltered and contains all the records included in the table
- A DataView does not contain copies of the table's rows. It is limited to storing an array of indexes that is updated whenever any of the filter properties are set
IMPORTANT PROPERTIES OF DATAVIEW CLASS
AllowDelete / AllowEdit / AllowNew | Get or set permissions to allow row operations in view |
ApplyDefaultSort | Permission to allow default sorting |
RowFilter | G/sets the expression used to filter out rows in the view |
Sort | G/sets the sorting of the view in terms of columns and order |
Table | G/sets the source DataTable for the view |
DataViewManager | Gets the DataViewManager object associated with this view |
IMPORTANT METHODS OF DATAVIEW CLASS
AddNew | Add a new row to the view and the underlying table |
BeginInit / EndInit | Begin / End initialization of the view, used for multiple changes |
Delete | Delete the row at specified index, deletes row in table too |
Find | Finds a row using specified key value |
FindRows | Returns an array of row objects that match specified key value |
GetEnumerator | Returns an enumerator object for the DataView |
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