这是我的代码:
HttpClient client = new HttpClient();
HttpResponseMessage response = await client.GetAsync("http://vk.com/video219171498_166049761");
string Vk_video_resText = await response.Content.ReadAsStringAsync();
txt.Text = "" + Vk_video_resText + "";
我该怎么拿
http:\\\/\\\/cs513404v4.vk.me\\\/u3692175\\\/videos\\\/b113808aad.360.mp4\
从 HTML 页面?