CellValueChangedイベントで値を保持しておけば良いのでは？
Public Class Form1
Private WithEvents DataGridView1 As New DataGridViewEx
Private WithEvents button As New Button
Private logTextBox As New TextBox
Sub New()
' この呼び出しはデザイナーで必要です。
InitializeComponent()
' InitializeComponent() 呼び出しの後で初期化を追加します。
DataGridView1.Columns.Add(New DataGridViewTextBoxColumn())
DataGridView1.Columns.Add(New DataGridViewTextBoxColumn())
DataGridView1.Dock = DockStyle.Fill
DataGridView1.Rows.Add()
DataGridView1.Rows.Add()
Me.Controls.Add(DataGridView1)
button.Text = "Test"
button.Dock = DockStyle.Bottom
Me.Controls.Add(button)
logTextBox.Dock = DockStyle.Bottom
logTextBox.Multiline = True
logTextBox.Height = 100
logTextBox.ScrollBars = ScrollBars.Both
Me.Controls.Add(logTextBox)
Me.DataGridView1.ReadOnly = True 'Readonlyやコンストラクタ内だとCellValidatingが発生しないことをテスト
Me.DataGridView1.Item(1, 0).Value = "てすとかいし"
End Sub
Private Sub DataGridView1_CellValueChanged2(sender As Object, e As DataGridViewCellEventArgsEx) Handles DataGridView1.CellValueChanged2
logTextBox.AppendText(String.Format("{0},{1}" & vbTab & "{0}" & vbTab & "{1}", e.RowIndex, e.ColumnIndex, e.OldValue, e.NewValue) & vbCrLf)
End Sub
Private Sub button_Click(sender As Object, e As EventArgs) Handles button.Click
Me.DataGridView1.Item(0, 0).Value = DateTime.Now.ToLongTimeString()
End Sub
End Class
Class DataGridViewEx
Inherits DataGridView
Public ReadOnly Property Buffer As DataGidViewValueBuffer
Get
Return _Buffer
End Get
End Property
Private _Buffer As DataGidViewValueBuffer
Sub New()
MyBase.New()
_Buffer = New DataGidViewValueBuffer(Me)
End Sub
Public Custom Event CellValueChanged2 As EventHandler(Of DataGridViewCellEventArgsEx)
AddHandler(ByVal value As EventHandler(Of DataGridViewCellEventArgsEx))
AddHandler _Buffer.CellValueChanged, value
End AddHandler
RemoveHandler(ByVal value As EventHandler(Of DataGridViewCellEventArgsEx))
RemoveHandler _Buffer.CellValueChanged, value
End RemoveHandler
RaiseEvent(ByVal sender As Object, ByVal e As DataGridViewCellEventArgsEx)
End RaiseEvent
End Event
End Class
Class DataGidViewValueBuffer
Public Event CellValueChanged As EventHandler(Of DataGridViewCellEventArgsEx)
Private _rowValueDicrionary As New Dictionary(Of DataGridViewRow, Dictionary(Of DataGridViewColumn, Object))
Private WithEvents _DataGridView As DataGridView
Public Sub New(ByVal dgv As DataGridView)
Me._DataGridView = dgv
End Sub
Public Property Item(ByVal clm As DataGridViewColumn, ByVal row As DataGridViewRow)
Get
Dim old As Object = Nothing
Dim rd As Dictionary(Of DataGridViewColumn, Object) = Nothing
If (_rowValueDicrionary.TryGetValue(row, rd)) Then
rd.TryGetValue(clm, old)
End If
Return old
End Get
Set(value)
Dim old As Object = Nothing
Dim rd As Dictionary(Of DataGridViewColumn, Object) = Nothing
If (Not _rowValueDicrionary.TryGetValue(row, rd)) Then
rd = New Dictionary(Of DataGridViewColumn, Object)()
_rowValueDicrionary.Add(row, rd)
End If
rd.Item(clm) = value
End Set
End Property
Private Sub _DataGridView_CellValueChanged(sender As Object, e As DataGridViewCellEventArgs) Handles _DataGridView.CellValueChanged
Dim row As DataGridViewRow = Me._DataGridView.Rows.Item(e.RowIndex)
Dim rd As Dictionary(Of DataGridViewColumn, Object) = Nothing
Dim clm As DataGridViewColumn = _DataGridView.Columns.Item(e.ColumnIndex)
Dim old As Object = Nothing
Dim [new] As Object = _DataGridView.Item(e.ColumnIndex, e.RowIndex).Value
If (_rowValueDicrionary.TryGetValue(row, rd)) Then
rd.TryGetValue(clm, old)
Else
rd = New Dictionary(Of DataGridViewColumn, Object)()
_rowValueDicrionary.Add(row, rd)
End If
Dim e2 As New DataGridViewCellEventArgsEx(e, _DataGridView, old, [new])
RaiseEvent CellValueChanged(_DataGridView, e2)
rd.Item(clm) = [new]
End Sub
Private Sub _DataGridView_RowsAdded(sender As Object, e As DataGridViewRowsAddedEventArgs) Handles _DataGridView.RowsAdded
Dim rd As New Dictionary(Of DataGridViewColumn, Object)
For i As Integer = e.RowIndex To e.RowIndex + e.RowCount - 1
Dim row As DataGridViewRow = _DataGridView.Rows.Item(i)
For Each clm As DataGridViewColumn In _DataGridView.Columns
Dim value As Object
value = row.Cells.Item(clm.Name).Value
If (value IsNot Nothing) Then
rd.Add(clm, value)
Dim e2 As New DataGridViewCellEventArgsEx(clm.Index, i, _DataGridView, Nothing, value)
RaiseEvent CellValueChanged(_DataGridView, e2)
End If
Next
_rowValueDicrionary.Add(row, rd)
Next
End Sub
Private Sub _DataGridView_RowsRemoved(sender As Object, e As DataGridViewRowsRemovedEventArgs) Handles _DataGridView.RowsRemoved
For Each row As DataGridViewRow In _rowValueDicrionary.Keys.ToArray().Where(Function(r) r.Index < 0)
_rowValueDicrionary.Remove(row)
Next
End Sub
Private Sub _DataGridView_ColumnRemoved(sender As Object, e As DataGridViewColumnEventArgs) Handles _DataGridView.ColumnRemoved
For Each rd As Dictionary(Of DataGridViewColumn, Object) In _rowValueDicrionary.Values
rd.Remove(e.Column)
Next
End Sub
End Class
Class DataGridViewCellEventArgsEx
Inherits DataGridViewCellEventArgs
Sub New(ByVal columnIndex As Integer, ByVal rowIndex As Integer, ByVal dataGridView As DataGridView, ByVal old As Object, ByVal newValue As Object)
MyBase.New(columnIndex, rowIndex)
Me.DataGridView = dataGridView
Me.OldValue = old
Me.NewValue = newValue
End Sub
Sub New(ByVal e As DataGridViewCellEventArgs, ByVal dataGridView As DataGridView, ByVal old As Object, ByVal newValue As Object)
MyClass.New(e.ColumnIndex, e.RowIndex, dataGridView, old, newValue)
End Sub
Public ReadOnly DataGridView As DataGridView
Public ReadOnly OldValue As Object
Public ReadOnly NewValue As Object
End Class
個別に明示されていない限りgekkaがフォーラムに投稿したコードにはフォーラム使用条件に基づき「MICROSOFT LIMITED PUBLIC LICENSE」が適用されます。(かなり自由に使ってOK!)
