StringFormat.SetDigitSubstitut...

protected override void OnPaint(PaintEventArgs e)
{
    base.OnPaint(e);
    SetDigitSubExample(e);
}

public void SetDigitSubExample(PaintEventArgs e)
{
    Graphics g = e.Graphics;
    SolidBrush blueBrush = new SolidBrush(Color.FromArgb(255, 0, 0, 255));
    Font myFont = new Font("Courier New", 12);
    StringFormat myStringFormat = new StringFormat();
    string myString = "0 1 2 3 4 5 6 7 8 9";

    // Farsi (1065) digits.

    // Use National substitution method.
    myStringFormat.SetDigitSubstitution(1065, StringDigitSubstitute.National);
    g.DrawString("Farsi:\nMethod of substitution = National:     " + myString, myFont, blueBrush, new PointF(10.0f, 20.0f), myStringFormat);

    // Use Traditional substitution method.
    myStringFormat.SetDigitSubstitution(1065, StringDigitSubstitute.Traditional);
    g.DrawString("Method of substitution = Traditional:  " + myString, myFont, blueBrush, new PointF(10.0f, 55.0f), myStringFormat);
}