WebClient client = new WebClient();
string url = "https://someurl.com/..."
string get = client.DownloadString(url);
如何计算已下载url
的次数?
答案 0 :(得分:1)
解决此问题的一种方法是继承WebClient
并覆盖要对其进行统计的方法。我已在以下实施中选择保留通过GetWebRequest
的任何网址的统计信息。我已经对代码进行了广泛的评论,因此我认为很清楚它可以归结为在字典中保持每Uri
的计数。
// subclass WebClient
public class WebClientWithStats:WebClient
{
// appdomain wide storage
static Dictionary<Uri, long> stats = new Dictionary<Uri, long>();
protected override WebResponse GetWebResponse(WebRequest request)
{
// prevent multiple threads changing shared state
lock(stats)
{
long count;
// do we have thr Uri already, if yes, gets its current count
if (stats.TryGetValue(request.RequestUri, out count))
{
// add one and update value in dictionary
count++;
stats[request.RequestUri] = count;
}
else
{
// create a new entry with value 1 in the dictionary
stats.Add(request.RequestUri, 1);
}
}
return base.GetWebResponse(request);
}
// make statistics available
public static Dictionary<Uri, long> Statistics
{
get
{
return new Dictionary<Uri, long>(stats);
}
}
}
典型的使用场景如下所示:
using(var wc = new WebClientWithStats())
{
wc.DownloadString("http://stackoverflow.com");
wc.DownloadString("http://stackoverflow.com");
wc.DownloadString("http://stackoverflow.com");
wc.DownloadString("http://meta.stackoverflow.com");
wc.DownloadString("http://stackexchange.com");
wc.DownloadString("http://meta.stackexchange.com");
wc.DownloadString("http://example.com");
}
var results = WebClientWithStats.Statistics;
foreach (var res in results)
{
Console.WriteLine("{0} is used {1} times", res.Key, res.Value);
}
将输出:
https://stackoverflow.com/使用3次 https://meta.stackoverflow.com/使用1次 http://stackexchange.com/使用1次 https://meta.stackexchange.com/使用1次 http://example.com/使用了1次
我认为pluralization bug是理所当然的。