WebClient client = new WebClient();
client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(Client_DownloadStringCompleted);
Uri token = new Uri("http://www.bing.com");
client.DownloadStringAsync(token);
更新:看起来是调试WP7时运行Fiddler造成的。Fiddler还破坏了模拟器上的浏览器。如果我找到使用Fiddler调试仿真器的解决方法,我将发布。