Currency conversion code issue

Question

Hi all, i am looking to convert dollar to local currency of my country (Cfa), i use combobox, the result i get example on the catch is wrong

 

here is my code: 

private void button2_Click(object sender, EventArgs e)
       {

            int selectIndex = dev1.SelectedIndex;


          int  money = int.Parse(mnt1.Text);
         int   rate = int.Parse(mnt2.Text);



           if (dev1.SelectedItem.ToString()=="Dollar" && dev2.SelectedItem.ToString()=="Cfa")

           {
               int conversion = money * rate;
               int convStr = Convert.ToInt32(conversion);
               total.Text = convStr.ToString();


      }

thank you for helping me see a little clearer