php 如何去除编辑器提交的空白字符

php 怎么去除编辑器提交的空白字符
就像这样的空白字符:

HTML code

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<p>    </p><div class="aritcle_card flexRow">
                                                        <div class="artcardd flexRow">
                                                                <a class="aritcle_card_img" href="/ai/2040" title="笔头写作"><img
                                                                                src="https://img.php.cn/upload/ai_manual/000/000/000/175680175114309.png" alt="笔头写作"  onerror="this.onerror='';this.src='/static/lhimages/moren/morentu.png'" ></a>
                                                                <div class="aritcle_card_info flexColumn">
                                                                        <a href="/ai/2040" title="笔头写作">笔头写作</a>
                                                                        <p>AI为论文写作赋能，协助你从0到1。</p>
                                                                </div>
                                                                <a href="/ai/2040" title="笔头写作" class="aritcle_card_btn flexRow flexcenter"><b></b><span>下载</span> </a>
                                                        </div>
                                                </div>

还原为实体是这样：

PHP code

$str = '<p>    </p>';
$result = htmlspecialchars_decode($str);
<br><font color="#e78608">------解决方案--------------------</font><br>

探讨

引用:

上个回答错了，被#2误导了，应该这样：

PHP code

$str = '

   

';
$result = htmlspecialchars_dec……