"steve" <ga630sf@newsgroups.nospam> schreef in bericht
news:eNrDUvpkGHA.1204@TK2MSFTNGP02.phx.gbl...
> Hi All
>
> I urgently need help on setting datagridview cell borders at runtime
>
> I found some code on the web from
> Programming Smart Client Data Applications with .NET 2.0
> by Brian Noyes
> See below
>
> This is what I have been trying to achieve, but when I run it ALL the cell
> Top borders go from inset to feint white on ALL cells, ALL rows
>
> If I change the line (marked *******) to false then the borders are OK but
> obviously no hiding of the required cell top borders
>
> I am completely lost on what is wrong
>
> Any help greatly appreciated
>
> Regards
> Steve
>
> Public Class GroupByGrid
>
> Inherits DataGridView
>
> Public Sub New()
>
> With Me
>
> .AdvancedCellBorderStyle.All = DataGridViewAdvancedCellBorderStyle.Inset
>
> End With
>
> End Sub
>
> Protected Overrides Sub OnCellFormatting(ByVal args As
> DataGridViewCellFormattingEventArgs)
>
> ' Call home to base
>
> MyBase.OnCellFormatting(args)
>
> ' First row always displays
>
> If args.RowIndex = 0 Then
>
> Return
>
> End If
>
> If IsRepeatedCellValue(args.RowIndex, args.ColumnIndex) Then
>
> args.Value = String.Empty
>
> args.FormattingApplied = True
>
> End If
>
> End Sub
>
> Private Function IsRepeatedCellValue(ByVal rowIndex As Integer, ByVal
> colIndex As Integer) As Boolean
>
> Dim currCell As DataGridViewCell = Rows(rowIndex).Cells(colIndex)
>
> Dim prevCell As DataGridViewCell = Rows(rowIndex - 1).Cells(colIndex)
>
> If Not IsNothing(currCell) AndAlso Not IsNothing(prevCell) AndAlso Not
> IsNothing(currCell.Value) AndAlso Not IsNothing(prevCell.Value) Then
>
> If (currCell.Value.ToString() = prevCell.Value.ToString() OrElse
> currCell.Value.Equals(prevCell.Value)) And prevCell.Value.ToString <>
> String.Empty And currCell.Value.ToString <> String.Empty Then
>
> Return true **********************************************
>
> Else
>
> Return False
>
> End If
>
> Else
>
> Return False
>
> End If
>
> End Function
>
> Protected Overrides Sub OnCellPainting(ByVal args As
> DataGridViewCellPaintingEventArgs)
>
> MyBase.OnCellPainting(args)
>
> ' Ignore column and row headers and first row
>
> If args.RowIndex < 1 OrElse args.ColumnIndex < 0 Then
>
> Return
>
> End If
>
> If IsRepeatedCellValue(args.RowIndex, args.ColumnIndex) Then
>
> args.AdvancedBorderStyle.Top = DataGridViewAdvancedCellBorderStyle.None
>
> Else
>
> args.AdvancedBorderStyle.Top = AdvancedCellBorderStyle.Top
>
> End If
>
>
>
> End Sub
>
> End Class
>
>

news:yu1JSwPlGHA.4928@TK2MSFTNGXA01.phx.gbl...
> Hi steve,
>
> Have you read my reply to you in your another post? You'd better override
> AdjustCellBorderStyle method to achieve this task. If you still have any
> concern, please feel free to followup me in that post. Thanks!
>
> Best regards,
> Jeffrey Tan
> Microsoft Online Community Support
> ==================================================
> When responding to posts, please "Reply to Group" via your newsreader so
> that others may learn and benefit from your issue.
> ==================================================
> This posting is provided "AS IS" with no warranties, and confers no
> rights.
>

news:ij7huoQmGHA.4928@TK2MSFTNGXA01.phx.gbl...
> Hi Steve,
>
> Have you recieved my sample project? Does it make sense to you? If you
> still need any help, please feel free to tell me.
>
> Additionally, I found that there is some strange performance issue in my
> sample project. After performing some debugging I found that changing
> DataGridView.AdvancedCellBorderStyle property in CellPainting event will
> generate another WM_PAINT message and send to DataGridView, which will
> force another painting in DataGridView(again calls CellPainting event ),
> so
> the DataGridView UI will keep painting all the time and have a flicker UI.
>
> To resolve this issue, you may place a ValidateRect Win32 calling in
> CellPainting event, which removes the WM_PAINT message in the message
> queue. Attached is the modified sample project, which works well now. Hope
> it helps!
>
> Best regards,
> Jeffrey Tan
> Microsoft Online Community Support
> ==================================================
> When responding to posts, please "Reply to Group" via your newsreader so
> that others may learn and benefit from your issue.
> ==================================================
> This posting is provided "AS IS" with no warranties, and confers no
> rights.

news:J9y4CG2mGHA.5268@TK2MSFTNGXA01.phx.gbl...
> Hi Steve,
>
> Thanks for your feedback!
>
> Oh, yes, I original tested the project in release build which can not see
> this error. By testing it under debugger, I can see this error. The error
> is caused by an improper API declaration: the second parameter to
> ValidateRect should be ByRef instead of ByVal. However, after correcting
> this error, it seems that it does not take effect. So it seems that
> ValidateRect can not remove WM_PAINT message from the message queue.
>
> Currently, I think the only valid solution is overriding
> AdjustCellBorderStyle method in DataGridViewCell and return a customized
> cell. I have written a sample project to demonstrate this technology,
> please see the attachment. Just click the button on the Form to see the
> effect.
>
> Hope it helps!
>
> Best regards,
> Jeffrey Tan
> Microsoft Online Community Support
> ==================================================
> When responding to posts, please "Reply to Group" via your newsreader so
> that others may learn and benefit from your issue.
> ==================================================
> This posting is provided "AS IS" with no warranties, and confers no
> rights.