• Xpath 获取html文档的标签


    1.html page content:
    <div class="mnr-c _yE">
        <div class="_kk _wI">In the news</div>
        <li class="card-section _df g _mZd">
            <div class="_K2 _SYd">
                <div style="overflow:hidden;134px;height:100px" class="thumb">
                <a href="http://www.bbc.co.uk/news/uk-30172110" onmousedown="return rwt(this,'','','','2','AFQjCNG3I0r8D75WjgjZODuobF8ne7wCNw','','0CCwQpwIwAQ','','',event)">
                    <img height="100" id="uid_0" src="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" width="134" border="0">
                </a>
                </div>
            </div>
            <div class="_I2">
                <a class="_Dk" href="http://www.bbc.co.uk/news/uk-30172110" onmousedown="return rwt(this,'','','','2','AFQjCNG3I0r8D75WjgjZODuobF8ne7wCNw','','0CC0QqQIwAQ','','',event)">
                Google case over online abuse settled</a>
                <div class="_Ck kv">
                    <cite>BBC News</cite><span class="f"> - </span>
                    <span class="f" style="white-space:nowrap">21 hours ago
                    </span>
                </div>
            </div>
            <span class="_dwd st s std" style="margin-left:144px">
            A UK businessman who took <em>Google</em> to court over malicious web postings about him&nbsp;...</span>
        </li>
        <div>
            <li class="g _Nn _wbb card-section">
                <a class="_Dk" href="http://www.pcworld.com/article/2851812/google-to-apps-users-take-more-responsibility-for-protecting-your-accounts.html" onmousedown="return rwt(this,'','','','3','AFQjCNH0fmBCNMjPanXErfX6GQmDNsZK7Q','','0CC8QqQIwAg','','',event)">
                New Google Apps dashboard helps users protect accounts</a>
                <div class="_Ck kv">
                    <cite>PCWorld</cite><span class="f"> - </span>
                    <span class="f" style="white-space:nowrap">5 hours ago</span>
                </div>
            </li>
            <li class="g _Nn _Abb card-section">
                <a class="_Dk" href="http://www.forbes.com/sites/georgeanders/2014/11/24/google-and-facebook-rewire-the-internet-as-fcc-dithers/" onmousedown="return rwt(this,'','','','4','AFQjCNGcPEbPFsUfSxeCneg_aFYBX65fNQ','','0CDEQqQIwAw','','',event)">
                Google And Facebook Rewire The Internet As FCC Dithers</a>
                <div class="_Ck kv">
                    <cite>Forbes</cite><span class="f"> - </span>
                    <span class="f" style="white-space:nowrap">8 hours ago</span>
                </div>
            </li>
        </div>

    2.获取标签:

    //获取文档中所有的class="g"或者包含"g"的<li>标签

    var allLiNodes = htmlDoc.DocumentNode.SelectNodes(@"//li[@class='g' or contains(@class,'g')]");

    //获取当前节点及其所有子节点中的具有先辈的<img>的单个<a>标签

    var imageNode = aImageTagNode.SelectSingleNode(@".//img[./ancestor::a/@href]");

    3.w3cshcool 实例:

    http://www.w3school.com.cn/xpath/xpath_axes.asp

    第一次接触,主要是对爬虫的结果进行解析,然后存储测试与发布,准确率还挺高的。

    另:若是浏览器,直接获取xpath的方法:

    F12  开发真工具,找到对应的元素,在标签上右键,就可以看到一个copy xpath 直接复制即可。

  • 相关阅读:
    【noip2011】选择客栈
    【noip2013】货车运输
    【bzoj3732】Network
    Codeforces 111C Petya and Spiders (状压dp)
    线段树优化 dijkstra (CF787D Legacy)
    Codeforces 908G Yet Another Maxflow Problem (最小割定理,线段树)
    IOI 2007 Sail (线段树+贪心)
    Codeforces 474E Pillars (树状数组+dp)
    Bzoj 3688 折线统计(dp+树状数组)
    Gorgeous Sequence (线段树)
  • 原文地址:https://www.cnblogs.com/shy-huang/p/4140127.html
Copyright © 2020-2023  润新知