从 html 个元素中抓取链接 - casperjs

Question

我目前正在尝试借助 casperjs 从这个 SITE 中抓取 link 和缩略图。我能够轻松地找出 html 结构（如下所示）。我正在尝试从所有 a 标签中提取在 href 属性中找到的 link。我运行我的脚本，但我收到 video_links 的错误。我怎样才能抓取所有 link 和缩略图并输出到一个数组中？错误

TypeError: 'undefined' is not an object (evaluating 'video_links.length')

脚本

var casper = require('casper').create({}),video_links,video_thumbnails;

//Functions
function getLinks() {
    var element = document.querySelectorAll('.cne-episode-block a');
    return Array.prototype.map.call(element, function(e) {
        return e.getAttribute('href');
    });
}
casper.start('http://video.wired.com/');

casper.then(function() {
    video_links = this.evaluate(getLinks);
});

casper.run( this.echo(video_links.length + ' links found.') );

HTML

<div class="cne-thumb-grid-container cne-context-container">
    <div class="cne-thumb cne-episode-block " data-videoid="551dc13461646d11aa020000">
        <div class="cne-thumb-image cne-rollover" data-powertiptarget="551dc13461646d11aa020000">
            <a class="cne-thumbnail cne-zoom-effect js-ajax-video-load" href="/watch/angry-nerd-will-netflix-s-daredevil-fly-or-flop" data-video-series="Angry Nerd" data-video-series-id="518d55c268f9dac897000003" data-video-id="551dc13461646d11aa020000" data-video-categories="[" Movies \u0026 TV "]">
                <img class="cne-video-thumb" src="http://dwgyu36up6iuz.cloudfront.net/heru80fdn/image/upload/c_fill,d_placeholder_thescene.jpg,fl_progressive,g_face,h_151,q_80,w_270/v1428076783/wired_angry-nerd-will-netflix-s-daredevil-fly-or-flop.jpg" alt="Will Netflixâ€™s Daredevil Fly or Flop?">
                <div class="cne-thumbnail-play">Play</div>
            </a>
        </div>
        <div class="cne-thumb-title the-thumb-title">
            <a class="js-ajax-video-load" href="/watch/angry-nerd-will-netflix-s-daredevil-fly-or-flop" data-video-id="551dc13461646d11aa020000">Will Netflixâ€™s Daredevil Fly or Flop?</a>
            <div class="cne-thumb-subtitle">
                <a href="/series/angry-nerd">Angry Nerd</a>
            </div>
        </div>
        <div id="551dc13461646d11aa020000" class="cne-thumb-rollover">
            <div class="cne-thumb-rollover-box">
                <span class="cne-rollover-category"> Movies & TV </span>
                <span class="cne-rollover-name"> Will Netflixâ€™s Daredevil Fly or Flop? </span>
                <span class="cne-rollover-description"> If Netflixâ€™s new Daredevil series is anything like Ben Affleckâ€™s Daredevil film, weâ€™re all in trouble. Angry Nerd explains what the latest incarnation needs to get right to make sure the man without fear doesnâ€™t turn into a total flop. </span>
            </div>
        </div>
    </div>
</div>

Answer 1

如果选择器在同一级别，则您只需要其中一个。因此，只需在您的 querySelectorAll 中使用 cne-thumb 或 cne-episode-block，而不是两者都使用。

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