silverlight中获取网页代码示例

在silverlight中如果要跨域访问，则需要在被访问网站的根目录下添加策略文件crossdomain.xml。内容如下（可以更细致配置，可以查阅相关资料）：

 <?xml version="1.0"?> <!-- <a href="http://code.js-code.com/tag/http/" target="_blank" class="keywords">http</a>://localhost/crossdomain.xml --> <cross-domain-policy> <allow-access-from domain="*" /> </cross-domain-policy>

在silverlight中使用webclient来获取网页内容，这里我简单封装了一个类。

需要using System.Net;

  public class SuperWeb<a href="http://code.js-code.com/tag/requ/" target="_blank" class="keywords">requ</a>est <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> public SuperWeb<a href="http://code.js-code.com/tag/requ/" target="_blank" class="keywords">requ</a>est(<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ng url,Delegate onComplet<a href="http://code.js-code.com/tag/E/" target="_blank" class="keywords">E)</a> <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> <a href="http://code.js-code.com/tag/requ/" target="_blank" class="keywords">requ</a>e<a href="http://code.js-code.com/tag/stu/" target="_blank" class="keywords">stu</a>RL = url; webClientOnCompet = onComplete; webClient.Download<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ngCompleted += new Download<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ngCompletedEventHandler(webClient_Download<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ngCompleted<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a> Random rand = new Random(<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a> bool add_flag = <a href="http://code.js-code.com/tag/fal/" target="_blank" class="keywords">fal</a>se; for (int i = 0; i < ur<a href="http://code.js-code.com/tag/l/" target="_blank" class="keywords">l.</a>Length; i++) <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> if (url[i] == '?') <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> add_flag = true; break; } } Uri endpoint; if (add_flag) endpoint = new Uri(url + "&rand=" + rand.Next()<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a> else endpoint = new Uri(url + "?rand=" + rand.Next()<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a>//<a href="http://code.js-code.com/tag/tianjia/" target="_blank" class="keywords">添加</a><a href="http://code.js-code.com/tag/suiji/" target="_blank" class="keywords">随机</a>数防止缓存 webClient.Download<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ngAsync(endpo<a href="http://code.js-code.com/tag/int/" target="_blank" class="keywords">int)</a>; } private void webClient_Download<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ngCompleted(ob<a href="http://code.js-code.com/tag/je/" target="_blank" class="keywords">je</a>ct sender,Download<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ngCompletedEventArgs <a href="http://code.js-code.com/tag/E/" target="_blank" class="keywords">E)</a> <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> if (!e.Cancelled && e.Error == null) <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> //回调 Super<a href="http://code.js-code.com/tag/o/" target="_blank" class="keywords">.o</a>bjMainPage.Dispatcher<a href="http://code.js-code.com/tag/b/" target="_blank" class="keywords">.b</a>eginInvoke(webClientOnCompet,e.Result.To<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ng()<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a> } else <a href="http://code.js-code.com/tag/" target="_blank" class="keywords">{</a> <a href="http://code.js-code.com/tag/messa/" target="_blank" class="keywords">messa</a>ge<a href="http://code.js-code.com/tag/Box/" target="_blank" class="keywords">Box</a>.Show("web通信异常" + e.Error.<a href="http://code.js-code.com/tag/messa/" target="_blank" class="keywords">messa</a>ge.To<a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ng()<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a> } } private WebClient webClient = new WebClient(<a href="http://code.js-code.com/tag/" target="_blank" class="keywords">);</a> private Delegate webClientOnCompet; private <a href="http://code.js-code.com/tag/Stri/" target="_blank" class="keywords">Stri</a>ng <a href="http://code.js-code.com/tag/requ/" target="_blank" class="keywords">requ</a>e<a href="http://code.js-code.com/tag/stu/" target="_blank" class="keywords">stu</a>RL; }

使用方法：

定义带模板委托

    public delegate void DelegateSingleParam<T>(T t);

调用

                SuperWebrequest myWebrequest = new SuperWebrequest(
                    Config.WebRoot+"lastvolumn.xml",new DelegateSingleParam<String>(OnLoadLastVolumn));

回调: data即网页代码

        private void OnLoadLastVolumn(String data)        {                    }