Public Class dgv_modificato
    Inherits System.Windows.Forms.DataGridView
    Dim riga As Integer
    Dim colonna As Integer
    Dim asd As DataGridViewCellValidatingEventArgs
    Protected Function non_so(ByVal sender As Object, ByVal e As DataGridViewCellValidatingEventArgs)
        asd = e
        Return (e)
    End Function
    Protected Overrides Function ProcessCmdKey(ByRef msg As System.Windows.Forms.Message, ByVal keyData As System.Windows.Forms.Keys) As Boolean
        Select Case colonna
            Case 0
                Select Case keyData
                    Case 48 To 57, 8
                        Me.Rows(riga).ErrorText = ""
                        dataGridView1_CellValidating(Me, asd)
                    Case Else
                        Me.Rows(riga).ErrorText = "sono ammessi solo numeri!!!"
                        msg = Nothing
                End Select
        End Select
        Return MyBase.ProcessCmdKey(msg, keyData)
    End Function
    Private Sub dataGridView1_CellBeginEdit(ByVal sender As Object, ByVal e As DataGridViewCellCancelEventArgs) Handles Me.CellBeginEdit
        riga = e.RowIndex
        colonna = e.ColumnIndex
    End Sub
    Private Sub dataGridView1_CellValidating(ByVal sender As Object, ByVal e As DataGridViewCellValidatingEventArgs)
        Select Case colonna
            Case 1
                Me.Rows(e.RowIndex).ErrorText = ""
                Dim Data As Date = Date.Today.ToString("dd/MM/yyyy")
                If Me.Rows(e.RowIndex).IsNewRow Then Return
                If Not Date.TryParse(e.FormattedValue.ToString(), Data) Then
                    Me.Rows(e.RowIndex).ErrorText = "La data deve essere nel formato ""dd/MM/yyyy"""
                    e.Cancel = True
                End If
        End Select
    End Sub
End Class