VB.NET -- Checkerboard in PictureBox

    Private Sub CheckerBoard()
 
        Dim rect As New Rectangle
 
        ' create a Graphics object to draw into it
        Dim pbox As Graphics = PictureBox1.CreateGraphics
        mSquWidth = PictureBox1.Width / CDbl(mCols)
        mSquHeight = PictureBox1.Height / CDbl(mRows)
        rect.Width = mSquWidth
        rect.Height = mSquHeight
 
        Dim r, c
        For r = 0 To mRows - 1
            For c = 0 To mCols - 1
                If ((r + c) Mod 2) = 0 Then
                    ' create a Graphics object to draw into it
                    pbox.FillRectangle(Brushes.Azure, rect)
                    pbox.DrawRectangle(Pens.Pink, rect)
                Else
                    pbox.FillRectangle(Brushes.BlueViolet, rect)
                    pbox.DrawRectangle(Pens.Red, rect)
                End If
                rect.X = c * mSquWidth
                rect.Y = r * mSquHeight
                ' create a Graphics object to draw into it
                pbox.FillRectangle(Brushes.BlueViolet, rect)
                pbox.DrawRectangle(Pens.Red, rect)
            Next
        Next
 
    End Sub