Only Double Number Textbox

private void textBox1_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;
}
}