DataView

A DataView is basically similar to a conventional database view, which is just a view of a datatable with different sorting and filtering criteria.
DataViews represent a customised view of a DataTable ideal for sorting, filtering, searching, editing etc

A DataView is similar to a live view on a DataTable, which allows programmers to set a sort order and filter on a view of the table.
This is just a view over an existing DataTable.
This gives you the same filtering and sorting capabilities as the DataTable.Select method.

Creating a DataView Object

Dim objDataView As System.Data.DataView 

objDataView = New System.Data.DataView 
objDataView.Table = objDataSet.Tables("Projects") 

Filtering Rows

This allows you to specify an expression similar to a SQL WHERE clause.

objDataView.RowFilter = "FirstName = 'Russell'"  
objDataView.RowFilter = "FirstName LIKE 'M*'"  
objDataView.RowFilter = "Len(LastName) > 8" 

objDataView.RowStateFilter = DataViewRowState.Deleted 

Sorting Rows

objDataView.Sort = "FirstName DESC" 

Adding and Deleting

You can add, delete and modify rows in a DataView by using the same methods you would use with the DataTable.

Total Rows

Gets the number of records in the DataView after RowFilter and RowStateFilter have been applied.

objDataView.Count 

Finding Data

You can also use the Find method to retrieve a DataRow given its primary key value.
Both these methods require that a primary key has been defined on the DataTable.
If the primary key exists then a DataRow object is returned. If the primary key does not exist then a Null value is returned.

objDataRow = objDataTable.Rows.Find(100) 

You can also use the Contains method to search for character-based single words or phrases.

bfound = objDataTable.Rows.Contains(100) 

You can also use the Find and FindRows methods of the DataView object.
Both these methods rely on the DataView being sorted by the column entry you are trying to find.

objDataView.Sort = "FirstName" 
iRowIndex = objDataView.Find("Russell") 

DataRowView Objects

A DataView contains a collection of DataRowView objects which are views over the rows in the underlying DataTable.

Dim objDataRowView As System.Data.DataRowView 
For Each objDataRowView In objDataTableConsolidation.DefaultView 
   sValue = objDataRowView.Item("ColumnName").ToString 
Next objDataRowView 

DataBinding

This binds the default DataView from a particular table and binds it to a DataGrid control.

Me.dgrDataGrid.DataSource = objDataSet.Tables("TableName").DefaultView 
Me.dgrDataGrid.DataBind(). 

This obtains the DataView that is associated with a DataGrid.

Dim objDataView As System.Data.DataView 
objDataView = CType(Me.dgrDataGrid.DataSource, System.Data.DataView) 

DataViewRowState Properties

Properties

Methods

Events