Question

这是我的代码

try
{
    for (int i = 0; i < RichTextbox2.Lines.Length; i++)
    {
        var length = urlwebapi.Lines.Length;
        {
            WebClient f = new WebClient();
            dynamic read = f.DownloadString(urlwebapi.Lines[(i % length)] + RichTextbox2.Lines[i]);
            JObject o = JObject.Parse(read);            
        }
    }
}
catch (WebException e)
{
    MessageBox.Show(e.Message);
}

MessageBox.Show("done");

示例urlwebapi

http://example1.com/api.php?ex=
http://example2.com/api.php?ex=
http://example3.com/api.php?ex=
http://example4.com/api.php?ex=
http://example5.com/api.php?ex=

代码只能同时在 urlwebapi 上运行一个。如何执行代码然后立即同时运行最多5个 urlwebapi （ example1.com直到example5.com ）

Answer 1

以下是如何操作的示例代码：

public async Task<string[]> DownloadStringsAsync(string[] urls)
    {
        var tasks = new Task<string>[urls.Length];
        for(int i=0; i<tasks.Length; i++)
        {
            tasks[i] = DownloadStringAsync(urls[i]);
        }
        return await Task.WhenAll(tasks);
    }

    public async Task<string> DownloadStringAsync(string url)
    {
        //validate!
        using(var client = new WebClient())
        {
            //optionally process and return
            return await client.DownloadStringTaskAsync(url)
                .ConfigureAwait(false);
        }
    }

我更喜欢使用HttpClient（https://msdn.microsoft.com/en-us/library/system.net.http.httpclient(v=vs.118).aspx），但流程基本相同

Answer 2

我建议使用httpClient。这使得它成为了parc的一个步行..并且使用你正确处理处置。

（伪代码）

using (var client = new httpClient)
{
  //your logic, and you can keep using client in this context.
}

如何同时运行多个WebClient？

2 个答案: