Private Sub frmMain_FormClosing(sender As Object, e As _
      System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        Dim IsEqual As Boolean = True
        For i = 0 To dtEngine.Rows.Count - 1
            If Not dtEngine.Rows(i).Item(2).Equals(dtUndo.Rows(i).Item(2)) Or _
              Not dtEngine.Rows(i).Item(3).Equals(dtUndo.Rows(i).Item(3)) Then
                IsEqual = False
            End If
        Next
 
        If IsEqual = False Then
            Dim Answer As MsgBoxResult
            Answer = MsgBox("You have made changes. Do you want to save the" & _
              "changes?", MsgBoxStyle.YesNo, "Changes made")
            If Answer = MsgBoxResult.Yes Then
                MsgBox("Saving")
            End If
        End If
 
    End Sub