. 
using System;
using System.IO;
using System.Net;
namespace DimPrawn.ASP.NET.Support
{
/// <summary>
/// Summary description for LookupCurrency.
/// </summary>
public class LookupCurrency
{
public LookupCurrency()
{
}
public decimal GetExchangeRate(string fromCurrencyCode, string toCurrencyCode)
{
decimal exchangeRate = 0.0m;
string url = string.Format(URL, fromCurrencyCode, toCurrencyCode);
Uri uri = new Uri(url);
string content = FetchPage(uri);
Numeric.IsNumber(content, out exchangeRate);
return exchangeRate;
}
private string FetchPage(Uri uri)
{
string content = null;
WebResponse response = null;
try
{
// Create a request for this uri
WebRequest request = WebRequest.Create(uri);
// First we only want to ge the HEADER to determine the type of resource at this url
request.Method = "HEAD";
// Fetch the response
response = request.GetResponse();
if ( response is HttpWebResponse )
{
_statusCode = ((HttpWebResponse)response).StatusCode.ToString();
_statusDescription = ((HttpWebResponse)response).StatusDescription;
if ( _statusCode.Equals( "OK" ) )
{
// read the headers
WebHeaderCollection headers = response.Headers;
// get the content type
string contentType = headers["Content-type"];
// If HTML, we will read the content
if (contentType.StartsWith("application/octet-stream"))
{
// Fetch full content
request = WebRequest.Create(uri);
// Fetch the response
response = request.GetResponse();
if ( response is HttpWebResponse )
{
_statusCode = ((HttpWebResponse)response).StatusCode.ToString();
_statusDescription = ((HttpWebResponse)response).StatusDescription;
if ( _statusCode.Equals( "OK" ) )
{
StreamReader sr = new StreamReader( response.GetResponseStream( ) );
content = sr.ReadToEnd( );
}
else
{
_errorCount++;
}
}
else
{
_errorCount++;
}
}
}
}
}
catch(Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.ToString());
_errorCount++;
}
finally
{
if (response != null)
{
response.Close();
}
}
return content;
}
private string _statusCode;
private string _statusDescription;
private int _errorCount;
private const string URL = "http://finance.yahoo.com/d/quotes.csv?s={0}{1}=X&f=a&e=.txt";
}
}
LookupCurrency currencyRate = new LookupCurrency();
Decimal exchangeRate = currencyRate.GetExchangeRate("GBP", "EUR");
Comment