What Problems Might the date_isodate_set Function Encounter When Handling Different Date Formats? How to Solve Them?

<span><span><span class="hljs-meta"><?php</span></span><span>
</span><span><span class="hljs-comment">// Irrelevant content at the beginning of the article</span></span><span>
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"This is the introduction to the article, demonstrating PHP code formatting.<br>"</span></span><span>;
</span><span><span class="hljs-variable">$time</span></span><span> = </span><span><span class="hljs-title function_ invoke__">time</span></span><span>();
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"Current timestamp: "</span></span><span> . </span><span><span class="hljs-variable">$time</span></span><span> . </span><span><span class="hljs-string">"<br>"</span></span><span>;
</span><span><span class="hljs-meta">?></span></span><span>
<p><hr></p>
<p></span><?php<br>
// Start of main content<br>
echo <span><span class="hljs-string">"<h2>What Problems Might the <code>date_isodate_set