But it seems not  work well. I set the defaultcellvalue in InitializeLayout ,and when a button click for call SetDataBinding. when DefaultCellValue = False ,it works well ,but when DefaultCellValue = True , it is not ok, it always show the False state. it is my test code.  by the way , when I set the column datatype as string , it is not work well yet.

    Private Sub UltraGrid1_InitializeLayout(ByVal sender As Object, ByVal e As Infragistics.Win.UltraWinGrid.InitializeLayoutEventArgs) Handles UltraGrid1.InitializeLayout

        UltraGrid1.DisplayLayout.AddNewBox.Hidden = False

        With e.Layout.Bands(0)
            If Not .Columns.Exists("COL1") Then
                .Columns.Add("COL1")
                .Columns("COL1").DataType = GetType(Boolean)
                .Columns("COL1").DefaultCellValue = True
            End If
            If Not .Columns.Exists("COL2") Then
                .Columns.Add("COL2")
                .Columns("COL2").DataType = GetType(String)
            End If
        End With
    End Sub

    Private Sub UltraButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles UltraButton1.Click
        UltraGrid1.SuspendLayout()

        Dim dt As New DataTable
        Dim dr As DataRow
        dt.Columns.Add("COL2", GetType(String))
        For i As Integer = 0 To 9
            dr = dt.NewRow
            dr.Item("COL2") = CStr(i + 4)
            dt.Rows.Add(dr)
        Next
        dt.AcceptChanges()
        UltraGrid1.SetDataBinding(dt, Nothing, True)

    End Sub

Hi,Mike

Yes, modify datasource column will definitely affect my business layer, I used your code, it runs perfect! I have tested performance(not very huge data) ,it's ok. Thanks very much Mike!

Jason

Hi Jason,

I wouldn't worry too much about performance unless you have a really huge number of rows. Anyway, there isn't any other way to do this - other than adding the column to your data source and giving the DataColumn a default value.

Hi, Mike

Really Great! I'm just a little concerned about performance cos the initialrow event is looped each row in my code.

Jason

Hi,

Sorry, it looks like DefaultCellValue only works for new rows. Try this:

    Private Sub UltraGrid1_InitializeRow(sender As System.Object, e As Infragistics.Win.UltraWinGrid.InitializeRowEventArgs) Handles UltraGrid1.InitializeRow
        If Not e.ReInitialize AndAlso e.Row.Cells.Exists("COL1") Then
            e.Row.Cells("Col1").Value = True
        End If
    End Sub