protected void btnmul_Click(object sender, EventArgs e)
 {
     lblresult.Text = ws.Mul(Convert.ToInt16(txtbox1.Text), Convert.ToInt16(txtbox2.Text)).ToString();
 }
 protected void btnMul_Click(object sender, EventArgs e)
 {
     lblResult.Text = calc.Mul(Convert.ToInt16(txtBoxA.Text), Convert.ToInt16(txtBoxB.Text)).ToString();
 }