Google Currency Converter

Question

I had used this code in the last years however google seemed to have changed some of their links. For some reason I am getting this error message:

"Input string was not in a correct format."

in following line:

decimal rate = System.Convert.ToDecimal(match.Groups[1].Value);

My code:

try
{
    WebClient web = new WebClient();
    string url = string.Format("https://www.google.com/finance/converter?a={2}&from={0}&to={1}", fromCurrency.ToUpper(), toCurrency.ToUpper(), amount);

    string response = web.DownloadString(url);

    Regex regex = new Regex("rhs: \\\"(\\d*.\\d*)");
    Match match = regex.Match(response);
    decimal rate = System.Convert.ToDecimal(match.Groups[1].Value);

    return rate;
}
catch
{
    return 0;
}

score 7 · Accepted Answer · edited Feb 16 '18 at 13:01

7

You may not like this approach but it get's the job done.

WebClient web = new WebClient();
string url = string.Format("https://www.google.com/finance/converter?a={2}&from={0}&to={1}", fromCurrency.ToUpper(), toCurrency.ToUpper(), amount);

string response = web.DownloadString(url);

var split  = response.Split((new string[] { "<span class=bld>"}),StringSplitOptions.None);
var value = split[1].Split(' ')[0];
decimal rate = decimal.Parse(value,CultureInfo.InvariantCulture);

edited Feb 16 '18 at 13:01

Gericke

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answered Aug 14 '15 at 15:57

Dimitris Batsougiannis

739
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12

Input string was not in a correct format. - same error :/ – Mark Fenech Aug 14 '15 at 16:04
it worked! Thanks...if I may ask, why shouldn't I like that approach? – Mark Fenech Aug 14 '15 at 16:18
1

@MarkFenech well some developers don't really like the string manipulation technique to extract data, but when it's for something like this I think it's ideal – Dimitris Batsougiannis Aug 14 '15 at 16:19

Google Currency Converter

1 Answers1