SetCount(Int32,Boolean) Method

Imports Infragistics.Shared
Imports Infragistics.Win
Imports Infragistics.Win.UltraWinDataSource


    Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles button1.Click
        Dim ds As UltraDataSource = New UltraDataSource()

        Dim col1 As UltraDataColumn = ds.Band.Columns.Add("ID", GetType(Integer))
        Dim col2 As UltraDataColumn = ds.Band.Columns.Add("Col2", GetType(String))

        Dim row As UltraDataRow
        Dim i As Integer
        For i = 0 To 5 - 1
            ' Look below where we call the Insert method for explanation on 
            ' what raiseAddEvents parameter does.
            row = ds.Rows.Add(True, New Object() {i, "Val " & i})
        Next

        ' Insert a row at index 0. A new row will be created and added to the
        ' collection at the specified index. RaiseAddEvents parameter of Add and
        ' Insert methods indicates whether the UltraDataSource should raise it's
        ' own RowAdding and RowAdded events. It does not indicate whether
        ' IBindingList.ListChanged event is raised or not.
        ' IBindingList.ListChanged event will always be raised regardless of the
        ' value of this parameter. This is useful when you have some logic in
        ' those event handlers for initializing new rows and you want that logic
        ' to be executed for the new row that you are inserting. If you use the
        ' overloads of Add or Insert that do not take raiseAddEvents parameter
        ' then add events won't be raised.
        row = ds.Rows.Insert(0, False, New Object() {-1, "Val -1"})

        ' Remove the inserted row. RaiseDeleteEvents parameter is analogous to
        ' the raiseAddEvents parameter of the Add and Insert methods. Look above
        ' where we call Insert for an explanation.
        row.ParentCollection.Remove(row, False)

        ' To check if a row is in a collection, use the Contains method.
        ' Following should print out false since the row has been deleted.
        Debug.WriteLine("Is deleted row in collection ? " & row.ParentCollection.Contains(row))

        ' A deleted row will have the index of -1. Following should print out -1
        ' since the row is not in the collection anymore. Row's Index property
        ' and IndexOf methods give the same results.
        Debug.WriteLine("Deleted row's index is " & row.Index)
        Debug.WriteLine("Deleted row's index is " & row.ParentCollection.IndexOf(row))

        ' You can also use the RemoveAt method to remove a row by specifying the 
        ' index of the row instead of the row itself.
        ds.Rows.RemoveAt(0, False)

        ' Print out the row count. This should print 4 as the row count since we
        ' added 5 using Add method in the for loop above and then added one
        ' using the Insert method above and then removed two using Remove and
        ' RemoveAt methods each.
        Debug.WriteLine("Row count = " & ds.Rows.Count)

        ' You can remove all rows from a row collection using Clear method. This
        ' is more efficient than deleting individual rows using Remove or
        ' RemoveAt methods.
        ds.Rows.Clear()

        ' You can use the SetCount method to add multiple rows at once. This can
        ' be more efficient than adding individual rows using Add method when
        ' adding a lot of rows.
        ds.Rows.SetCount(5)

        ' Add another 5 rows by setting the count to 10. Previously we added 5
        ' rows when we called SetCount( 5 ) above. Calling SetCount with 10 will
        ' add another 5 rows so that the new count becomes 10.
        ds.Rows.SetCount(10)

        ' Following line should print out 10.
        Debug.WriteLine("Row count = " & ds.Rows.Count)

        ds.Rows.SetCount(100000)

        ' Following line should print out 100000.
        Debug.WriteLine("Row count = " & ds.Rows.Count)
    End Sub