private void button1_Click(object sender, EventArgs e) { SimpleServiceClient loclient = new SimpleServiceClient(); int num1 = Convert.ToInt32(txtnum1.Text); int num2 = Convert.ToInt32(txtnum2.Text); if (comboBox1.Text == "ADD") { textBox1.Text = (loclient.Add(num1, num2)).ToString(); } else if (comboBox1.Text == "SUBSTRACT") { textBox1.Text = loclient.Substract(num1, num2).ToString(); } else if (comboBox1.Text == "MULTIPLY") { textBox1.Text = loclient.Multiply(num1, num2).ToString(); } else if (comboBox1.Text == "DIVIDE") { textBox1.Text = loclient.Divide(num1, num2).ToString(); } }