private void txtBoxDiscount_Click(object sender, EventArgs e)
{
FormCalculator calculator = new FormCalculator(txtBoxDiscount);
calculator.ShowDialog();
}
private void txtProductPrice_EditItems_Click(object sender, EventArgs e)
{
FormCalculator numpad = new FormCalculator(txtProductPrice_EditItems);
numpad.ShowDialog();
}
private void txtBoxPrice_Click(object sender, EventArgs e)
{
FormCalculator numpad = new FormCalculator(txtBoxPrice);
numpad.ShowDialog();
}