title: Unit test with nUnit and nMocks
body: <p>Bit of a nUnit / nMock / Unit testing noobie question:</p>
  
  <p>I am trying to unit test this class. </p>
  
  <p>I have created a mock of it because I want to know the value returned from "getCurrencyRates", so that I can create tests based on that data.</p>
  
  <p>So I created a mock of this object (just to be able to know the exchange rates returned).</p>
  
  <p>...but now I also want to call some of the other methods on this class.</p>
  
  <p>Should I:</p>
  
  <p>a) somehow call the real methods from the mock object (not even sure if that's possible)
  b) refactor so that only the web service call is in it's own object and create a mock of that
  c) something else?</p>
  
  <pre><code>public class CurrencyConversion : ICurrencyConversion
  {
      public decimal convertCurrency(string fromCurrency, string toCurrency, decimal amount)
      {
  
          CurrencyRateResponse rates = getCurrencyRates();
          var fromRate = getRate(rates, fromCurrency);
          var toRate = getRate(rates, toCurrency);
  
          decimal toCurrencyAmount = toRate / fromRate * amount;
  
          return toCurrencyAmount;
      }
  
  
      public int addNumbers(int i, int j)
      {
          return i + j;
  
      }
  
      public decimal getRate(CurrencyRateResponse rates, string fromCurrency)
      {
  
          if (rates.rates.ContainsKey(fromCurrency))
          {
              return rates.rates[fromCurrency];
          }
          else
          {
              return 0;
          }
      }
      public CurrencyRateResponse getCurrencyRates()
      {
          HttpWebRequest webRequest = GetWebRequest("http://openexchangeerates.org/latest.json");
  
          HttpWebResponse response = (HttpWebResponse)webRequest.GetResponse();
          string jsonResponse = string.Empty;
          using (StreamReader sr = new StreamReader(response.GetResponseStream()))
          {
              jsonResponse = sr.ReadToEnd();
          }
  
          var serializer = new JavaScriptSerializer();
          CurrencyRateResponse rateResponse = serializer.Deserialize&lt;CurrencyRateResponse&gt;(jsonResponse);
  
          return rateResponse;
  
      }
      public HttpWebRequest GetWebRequest(string formattedUri)
      {
          // Create the request’s URI.
          Uri serviceUri = new Uri(formattedUri, UriKind.Absolute);
  
          // Return the HttpWebRequest.
          return (HttpWebRequest)System.Net.WebRequest.Create(serviceUri);
      }
  }
  </code></pre>