使用 preg_replace 从表元素中删除所有高度标签/属性？

Question

In our system, users often copy/paste tables from other sources, such as Excel/Word, which results in tables that have height tags or attributes in a number of places. I was thinking I could use pattern matching (preg_replace) to find and remove those instances as the inclusion of height specifications is causing issues in our system when this HTML is used by our PHP API to output formatted reports, but I've been trying to do so for the last 3 days without much success as I'm not adept at using regular expressions in this way.

I've read the documentation and examples on php.net and reviewed quite a few of the posts here on this topic, but I still don't know how to only apply the pattern matching to only instances within a tag, etc.

Also, how would I remove the entire tag if it only includes a height attribute, and then only the height attribute if other attributes are included?

Here is an example of the code I need to clean. This is just a small portion, as it typically will include multiple table elements similar to what's I've included below, along with images, text, etc.:

<table style="height:126px;" width="243">
    <tbody>
        <tr style="height: 18px;">
            <td style="width: 38.5px; height: 18px;">ABC</td>
            <td style="width: 41.5469px; height: 18px;">123</td>
            <td style="width: 50.6562px; height: 18px;">DEF;</td>
            <td style="width: 99.2969px; height: 18px;">456</td>
        </tr>
            <tr style="height:18px;">
            <td style="width: 38.5px; height: 18px;">GHI</td>
            <td style="width: 41.5469px; height: 18px;">789</td>
            <td style="width: 50.6562px; height: 18px;">JKL</td>
            <td style="width: 99.2969px; height: 18px;">012</td>
        </tr>
            <tr style="height:18px;">
            <td style="width: 38.5px; height: 18px;">MNO</td>
            <td style="width: 41.5469px; height: 18px;">345</td>
            <td style="width: 50.6562px; height: 18px;">PQR</td>
            <td style="width: 99.2969px; height: 18px;">678</td>
        </tr>
    </tbody>
</table>

Can this be done using preg_replace, or do I need to use a different technique? Any guidance or assistance would be greatly appreciated. A "cleaned" version of the above would look like this:

Cleaned

<table width="243">
    <tbody>
        <tr>
            <td style="width: 38.5px;">ABC</td>
            <td style="width: 41.5469px;">123</td>
            <td style="width: 50.6562px;">DEF;</td>
            <td style="width: 99.2969px;">456</td>
        </tr>
            <tr>
            <td style="width: 38.5px;">GHI</td>
            <td style="width: 41.5469px;">789</td>
            <td style="width: 50.6562px;">JKL</td>
            <td style="width: 99.2969px;">012</td>
        </tr>
            <tr>
            <td style="width: 38.5px;">MNO</td>
            <td style="width: 41.5469px;">345</td>
            <td style="width: 50.6562px;">PQR</td>
            <td style="width: 99.2969px;">678</td>
        </tr>
    </tbody>
</table>

Answer 1

Have you considered simply swapping the 'height:' style attribute with a non-existent one (ie: the DOM will ignore unknown tags); for example:

$str = '<table style="height:126px;" width="243">
    <tbody>
        <tr style="height: 18px;">
            <td style="width: 38.5px; height: 18px;">ABC</td>
            <td style="width: 41.5469px; height: 18px;">123</td>
            <td style="width: 50.6562px; height: 18px;">DEF;</td>
            <td style="width: 99.2969px; height: 18px;">456</td>
        </tr>
            <tr style="height:18px;">
            <td style="width: 38.5px; height: 18px;">GHI</td>
            <td style="width: 41.5469px; height: 18px;">789</td>
            <td style="width: 50.6562px; height: 18px;">JKL</td>
            <td style="width: 99.2969px; height: 18px;">012</td>
        </tr>
            <tr style="height:18px;">
            <td style="width: 38.5px; height: 18px;">MNO</td>
            <td style="width: 41.5469px; height: 18px;">345</td>
            <td style="width: 50.6562px; height: 18px;">PQR</td>
            <td style="width: 99.2969px; height: 18px;">678</td>
        </tr>
    </tbody>
</table>';

$str = str_replace("height:","nulled:",$str);

echo $str;

I took your table HTML, put it into a string variable and did a simple str_replace to swap all references to height: to nulled: which strips the height attribute out the string and when I echo the string back I get the cleaned table you put in your example.

There may be an even prettier approach, but this worked for me. :)