在c＃中向EventHandler添加一些参数

Question

By now I'm having this code

public void getRankingList(string country,string type)
    {            
        WebClient client = new WebClient();
        client.AllowReadStreamBuffering = true;
        string url = "......";
        client.DownloadStringCompleted += getRankingResult;
        client.DownloadStringAsync(new Uri(url, UriKind.Absolute));
    }
private void getRankingResult(object sender, DownloadStringCompletedEventArgs e)
    {
        .........
    }

So now can I add some para to the downloadCompleted event ? something like:

private void getRankingResult(object sender, DownloadStringCompletedEventArgs e, string Para)
    {
        .........
    }

Answer 1

public void getRankingList(string country,string type)
    {            
        WebClient client = new WebClient();
        client.AllowReadStreamBuffering = true;
        string url = "......";
        client.DownloadStringCompleted += (sender, args) => 
        getRankingResult(sender, args, "para");
        client.DownloadStringAsync(new Uri(url, UriKind.Absolute));
    }

private void getRankingResult(object sender, DownloadStringCompletedEventArgs e, string Para)
{
    // .....
}

Answer 2

如果DownloadStringCompletedEventArgs不是密封类，那么您可以创建一个新类并从中继承并向其添加附加string Para字段。