我正在尝试构建一个函数，该函数将清除HTML文档中所有内容为空或没有属性的元素，并且我想取消<br>和<hr>标记。
这是我当前的代码。
<?php
function clean($html){
$dom = new DOMDocument();
$dom->loadHTML($html)
$xpath = new DOMXPath($dom);
while (($node_list = $xpath->query('//*[not(*) and not(@*) and not(text()[normalize-space()])]')) && $node_list->length) {
foreach ($node_list as $node) {
$node->parentNode->removeChild($node);
}
}
return $dom->saveHTML();
}
如何使用xpath查询忽略br和hr来选择所有节点。
示例输入：
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<p><strong><span style="font-size:16px;">Specifications:</span></strong><br>
<span style="font-size:16px;">1. Material: Polymer</span><br>
<span style="font-size:16px;">2. Weight: 7.94oz / 225g</span><br>
<span style="font-size:16px;">3. Color: <strong><span style="color:#ff0000;background-color:#ffffff;">Black / White / Blue /</span></strong> <strong><span style="color:#ff0000;background-color:#ffffff;">Red</span></strong></span><br>
<span style="font-size:16px;">4. Dimensions: (7.48 x 7.87 x 3.35)" / (19 x 20 x 8.5)cm (L x W x H)</span><br>
<span style="font-size:16px;">5. Driver Unit: 2 Speakers(57mm)</span><br>
<span style="font-size:16px;">6. Transducer Type: Dynamic</span><br>
<span style="font-size:16px;">7. Bluetooth Version: V4.1</span><br>
<span style="font-size:16px;">8. Operating Distance: up to 10m(Free Space)</span><br>
<span style="font-size:16px;">9. Profiles: A2DP,AVRCP,HSP,HFP</span><br>
<span style="font-size:16px;">10. Speaker Impendence: 16Ω</span><br>
<span style="font-size:16px;">11. Frequency Response: 20Hz-20KHz</span><br>
<span style="font-size:16px;">12. Sensitivity: 110dB</span><br>
<span style="font-size:16px;">13. THD: <0.1%</span><br>
<span style="font-size:16px;">14. <span style="color:#6600ff;">Support Micro SD Card Capacity</span>: up to 32GB</span><br>
<span style="font-size:16px;">15. Micro SD Card Play Time: about 15 hours</span><br>
<span style="font-size:16px;">16. FM Play Time: about 15 hours</span><br>
<span style="font-size:16px;">17. Bluetooth Music Time: about 40 hours</span><br>
<span style="font-size:16px;">18. Talk Time: about 45 hours</span><br>
<span style="font-size:16px;">19. Standby Time: 1620 hours(around 50Days)</span><br>
<span style="font-size:16px;">20. Fully Charged Time: about 2 hours</span><br>
<span style="font-size:16px;">21. Operating Environment: -10~50℃</span></p><span style="font-size:16px;"></span>
<ul>
<li><span style="font-size:16px;"></span></li>
<li><span style="font-size:16px;"></span></li>
<li><span style="font-size:16px;"></span></li>
</ul>
<p></p>
</body>
</html>
由于一些原因，没有人知道这有这个部分没有内容：
我想删除它，同时保留特征线。
电流输出示例：
<html>
<head>
<title></title>
</head>
<body>
<p><strong><span style="font-size:16px;">Specifications:</span></strong> <span style="font-size:16px;">1. Material: Polymer</span> <span style="font-size:16px;">2. Weight: 7.94oz / 225g</span> <span style="font-size:16px;">3. Color: <strong><span style="color:#ff0000;background-color:#ffffff;">Black / White / Blue /</span></strong> <strong><span style="color:#ff0000;background-color:#ffffff;">Red</span></strong></span> <span style="font-size:16px;">4. Dimensions: (7.48 x 7.87 x 3.35)" / (19 x 20 x 8.5)cm (L x W x H)</span> <span style="font-size:16px;">5. Driver Unit: 2 Speakers(57mm)</span> <span style="font-size:16px;">6. Transducer Type: Dynamic</span> <span style="font-size:16px;">7. Bluetooth Version: V4.1</span> <span style="font-size:16px;">8. Operating Distance: up to 10m(Free Space)</span> <span style="font-size:16px;">9. Profiles: A2DP,AVRCP,HSP,HFP</span> <span style="font-size:16px;">10. Speaker Impendence: 16Ω</span> <span style="font-size:16px;">11. Frequency Response: 20Hz-20KHz</span> <span style="font-size:16px;">12. Sensitivity: 110dB</span> <span style="font-size:16px;">13. THD: <0.1%</span> <span style="font-size:16px;">14. <span style="color:#6600ff;">Support Micro SD Card Capacity</span>: up to 32GB</span><span style="font-size:16px;">15. Micro SD Card Play Time: about 15 hours</span> <span style="font-size:16px;">16. FM Play Time: about 15 hours</span> <span style="font-size:16px;">17. Bluetooth Music Time: about 40 hours</span> <span style="font-size:16px;">18. Talk Time: about 45 hours</span><span style="font-size:16px;">19. Standby Time: 1620 hours(around 50Days)</span><span style="font-size:16px;">20. Fully Charged Time: about 2 hours</span><span style="font-size:16px;">21. Operating Environment: -10~50℃</span></p>
</body>
</html>
所需输出示例：
<html>
<head>
<title></title>
</head>
<body>
<p><strong><span style="font-size:16px;">Specifications:</span></strong><br>
<span style="font-size:16px;">1. Material: Polymer</span><br>
<span style="font-size:16px;">2. Weight: 7.94oz / 225g</span><br>
<span style="font-size:16px;">3. Color: <strong><span style="color:#ff0000;background-color:#ffffff;">Black / White / Blue /</span></strong> <strong><span style="color:#ff0000;background-color:#ffffff;">Red</span></strong></span><br>
<span style="font-size:16px;">4. Dimensions: (7.48 x 7.87 x 3.35)" / (19 x 20 x 8.5)cm (L x W x H)</span><br>
<span style="font-size:16px;">5. Driver Unit: 2 Speakers(57mm)</span><br>
<span style="font-size:16px;">6. Transducer Type: Dynamic</span><br>
<span style="font-size:16px;">7. Bluetooth Version: V4.1</span><br>
<span style="font-size:16px;">8. Operating Distance: up to 10m(Free Space)</span><br>
<span style="font-size:16px;">9. Profiles: A2DP,AVRCP,HSP,HFP</span><br>
<span style="font-size:16px;">10. Speaker Impendence: 16Ω</span><br>
<span style="font-size:16px;">11. Frequency Response: 20Hz-20KHz</span><br>
<span style="font-size:16px;">12. Sensitivity: 110dB</span><br>
<span style="font-size:16px;">13. THD: <0.1%</span><br>
<span style="font-size:16px;">14. <span style="color:#6600ff;">Support Micro SD Card Capacity</span>: up to 32GB</span><br>
<span style="font-size:16px;">15. Micro SD Card Play Time: about 15 hours</span><br>
<span style="font-size:16px;">16. FM Play Time: about 15 hours</span><br>
<span style="font-size:16px;">17. Bluetooth Music Time: about 40 hours</span><br>
<span style="font-size:16px;">18. Talk Time: about 45 hours</span><br>
<span style="font-size:16px;">19. Standby Time: 1620 hours(around 50Days)</span><br>
<span style="font-size:16px;">20. Fully Charged Time: about 2 hours</span><br>
<span style="font-size:16px;">21. Operating Environment: -10~50℃</span></p>
</body>
</html>
提前谢谢。
严格来说，这个XPath将从您的主体中选择空节点(保留br、hr和strong元素(。
//body//*[name()!='br' and name()!='hr' and name()!='strong'][string(normalize-space())='']
输出：9个节点。