从HTML中提取/抓取值

Question

我想创建一个脚本，从城市网站上发布的这个糟糕的HTML中抓取两个值：

558.35

和

66.0

这些是水库的细节，每周更换一次。

我不确定这样做的最佳工具是什么，grep？

感谢您的建议，想法！

<table>
    <tbody>
        <tr>
            <td>&nbsp;Currently:</td>
            <td>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 558.35</td>
        </tr>
        <tr>
            <td>&nbsp;Percent of capacity:</td>
            <td>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;66.0%</td>
        </tr>
    </tbody>
</table>

Answer 1

如果您使用的是正则表达式，则可以使用sed

sed -nr 's#^[ ]*<td>.*;[ ]?([0-9]+[.][0-9]+)[%]?</td>[ ]*$#\1#p' my_html_file

一个Htmlparser如python的模块BeautifulSoup或javascript方法是一个更安全的选择

修改

这是一个使用javascript的片段。结果会记录到控制台并弹出一个警告框以显示结果

var values="";
for(i=1;i<document.getElementsByTagName('td').length;++i){
values+=" "+document.getElementsByTagName('td')[i].innerHTML.replace(/&nbsp;|Percent of capacity:|[ %]/g,"")
}
alert(values);
console.log(values);

<table>
    <tbody>
        <tr>
            <td>&nbsp;Currently:</td>
            <td>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 558.35</td>
        </tr>
        <tr>
            <td>&nbsp;Percent of capacity:</td>
            <td>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;66.0%</td>
        </tr>
    </tbody>
</table>