private void btn_multiplier_Click(object sender, EventArgs e) { a = Convert.ToInt32(txtb_intA.Text); b = Convert.ToInt32(txtb_intB.Text); if (rbtn_default.Checked) { Multiplier = new Context(new MultiplyStratA()); } else if (rbtn_recursive.Checked) { Multiplier = new Context(new MultiplyStratB()); } else { Multiplier = new Context(new MultiplyStratC()); } lbl_result.Text = Multiplier.ContextMultiplier(a, b).ToString(); }