European Central Bank- part 8
Because I have had last time a flop, now I decide to get the European Central Bank rates.
Going to https://www.ecb.europa.eu/stats/policy_and_exchange_rates/euro_reference_exchange_rates/html/index.en.html show the XML – but not the XSD.
So now it is about how to transform from XML to C# classes – and I remembered a discussion with https://siderite.dev/ – Visual Studio does now how to paste from XML to classes. ( Edit=>PasteSpecial +> Paste XML as classes. Ensure that you have not space on the first line…)
Copy and paste fron BNR class, modify the URL to https://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml
Now the program.cs looks like this
var nbr = new GetNBRExchange();
var list = nbr.GetActualRates();
await foreach (var e in list)
{
Console.WriteLine($"1 {e.ExchangeFrom} = {e.ExchangeValue} {e.ExchangeTo}");
}
var ecb = new GetECBExchange();
list = ecb.GetActualRates();
await foreach (var e in list)
{
Console.WriteLine($"1 {e.ExchangeFrom} = {e.ExchangeValue} {e.ExchangeTo}");
}
See the similarities ?
It is time for some interfaces . The simplest one is
public interface BankGetExchange
{
IAsyncEnumerable<ExchangeRates> GetActualRates();
}
And now the Program.cs looks like
static async Task Main(string[] args)
{
await ShowValues(new GetNBRExchange());
await ShowValues(new GetECBExchange());
}
public static async Task ShowValues(BankGetExchange bank)
{
var list = bank.GetActualRates();
await foreach (var e in list)
{
Console.WriteLine($"1 {e.ExchangeFrom} = {e.ExchangeValue} {e.ExchangeTo}");
}
}
and seems better now!
What can be improved ? Well , to process both in parallel ( now they are processed one after another)
Another condition is not to display intermixed. So the code could stay like
So I ended with the following:
using InfoValutarShared;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Threading.Tasks;
using System.Xml.Serialization;
namespace InfoValutarDOS
{
class Program
{
static async Task Main()
{
var l = new List<Task<ExchangeRates[]>>
{
Rates(new GetNBRExchange()),
Rates(new GetECBExchange()),
};
while (l.Count > 0)
{
var x = l.ToArray();
var data = await Task.WhenAny(x);
ShowValues(await data);
l.Remove(data);
}
}
public static async Task<ExchangeRates[]> Rates(BankGetExchange bank)
{
var list = bank.GetActualRates();
return await list.ToArrayAsync();
}
public static void ShowValues(ExchangeRates[] list)
{
foreach (var e in list)
{
Console.WriteLine($"1 {e.ExchangeFrom} = {e.ExchangeValue} {e.ExchangeTo}");
}
}
}
}
Infovalutar
And one hour passes...(This is the result of 1 hour per day auto-challenge as a full cycle developer for an exchange rates application)
( You can see the sources at https://github.com/ignatandrei/InfoValutar/ )