如何從C＃中的視頻嵌入代碼中提取直接視頻URL？

我有一個視頻嵌入代碼爲類似於Youtube的視頻託管網站上的一個視頻生成。我需要提取直接鏈接到視頻源（* .m4v）。在這個例子下面我想提取值「http://play.op.ac.nz/images/media/beb431bc59587dc71e10939d214e9515_1315897772.m4v」，並將其放置在一個字符串：如何從C＃中的視頻嵌入代碼中提取直接視頻URL？

<script type="text/javascript" src="http://play.op.ac.nz/js/embed.js.php?key=beb431bc59587dc71e10939d214e9515"></script> 
<noscript> 
    <!-- Version SVN: $Id: _playerVideo.php 19008 2011-05-17 19:06:32Z sven $ --> 
    <div id="flash"> 
    <div id="flashcontent"> 
     <object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" id="flvplayer_4e71fa175218d" name="c6a80378-3eb2-47e7-8415-ba1f7cff037e" width="720" height="406" style="position:relative;top:0;left:0;z-index:9999;"> 
     <param name="movie" value="http://play.op.ac.nz/flash/vimp.swf" /> 
     <param name="flashvars" value="hosturl=http%3A%2F%2Fplay.op.ac.nz%2Fmedia%2Fflashcomm&amp;mediaid=195&amp;context=embeded&amp;skin=http%3A%2F%2Fplay.op.ac.nz%2Fflash%2Fskins%2Fice_white.swf&amp;autohidesidebaronplay=true" /> 
     <param name="scale" value="true" /> 
     <param name="allowfullscreen" value="true" /> 
     <param name="allowscriptaccess" value="always" /> 
     <param name="wmode" value="opaque" /> 
     <!--[if !IE]>--> 
     <object type="application/x-shockwave-flash" data="http://play.op.ac.nz/flash/vimp.swf" width="720" height="406" wmode="opaque"> 
      <param name="flashvars" value="hosturl=http%3A%2F%2Fplay.op.ac.nz%2Fmedia%2Fflashcomm&amp;mediaid=195&amp;context=embeded&amp;skin=http%3A%2F%2Fplay.op.ac.nz%2Fflash%2Fskins%2Fice_white.swf&amp;autohidesidebaronplay=true" /> 
      <param name="scale" value="true" /> 
      <param name="allowfullscreen" value="true" /> 
      <param name="allowscriptaccess" value="always" /> 
      <param name="wmode" value="opaque" /> 
      <!--<![endif]--> 
      <div class="leanback-player-video"> 
      <video id="index_video" width="720" height="406" preload="metadata" controls="" poster="http://play.op.ac.nz/cache/99590fa59570e38b09e63000c99a6859.jpg"> 
       <source src="http://play.op.ac.nz/images/media/beb431bc59587dc71e10939d214e9515_1315897772.m4v" type="video/mp4" /> 
       <source src="http://play.op.ac.nz/images/media/beb431bc59587dc71e10939d214e9515_1315897772.webm" type="video/webm" /> 
       <source src="http://play.op.ac.nz/images/media/beb431bc59587dc71e10939d214e9515_1315897772.ogv" type="video/ogg" /> 
       <p style="margin: 15px;"> 
       Hint: Unfortunately your browser does not have Flash Player installed or the Flash Player version is outdated. You need Flash Player to view media in this community. <a href="http://www.macromedia.com/go/getflashplayer">Download Flash Player</a> 
       </p> 
       <img alt="How to safely operate a power actuated nail gun" title="How to safely operate a power actuated nail gun" src="http://play.op.ac.nz/cache/99590fa59570e38b09e63000c99a6859.jpg" /> 
      </video> 
      </div> 
      <!--[if !IE]>--> 
     </object> 
     <!--<![endif]--> 
     </object> 
    </div> 
    </div> 
</noscript>

我已經已經完成了搜索並在PHP和Python中找到了很多解決方案，但沒有任何可以解釋的東西。我有一段時間沒有碰到C＃，所以任何幫助，將不勝感激。

來源

2011-09-15 Anton Smith