C# TextBox Numeric Value with one decimal point

private void txtBasicSal_KeyPress(object sender, KeyPressEventArgs e)

        {

            if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar)&& e.KeyChar != '.')

            {

                e.Handled = true;

            }

            // only allow one decimal point

            if (e.KeyChar == '.'&& (sender as TextBox).Text.IndexOf('.') > -1)

            {

                e.Handled = true;

            }

        }