
1: class Operation
2: {3: public virtual double operation(int x, int y)
4: {5: return x * y;
6: } 7: }8: class Addition : Operation
9: {10: public override double operation(int x, int y)
11: {12: return (x + y);
13: } 14: } 15: 16: private void button1_Click(object sender, EventArgs e)
17: {18: if (comboBox1.SelectedIndex == 0)
19: {20: Operation multiplication = new Operation();
21: txtResult.Text = multiplication.operation( Convert.ToInt32(txtNum1.Text.Trim()), Convert.ToInt32(txtNum2.Text.Trim() )).ToString(); 22: }23: else
24: {25: Operation addition = new Addition();
26: txtResult.Text = addition.operation(Convert.ToInt32(txtNum1.Text.Trim()), Convert.ToInt32(txtNum2.Text.Trim())).ToString(); 27: }28: }








