How to get the caret column (not pixels) position in a textarea, in characters, from the start?

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时光说笑 2020-11-21 06:41

How do you get the caret position in a </code> using JavaScript?</p> <p>For example: <code>This is| a text</code></p> <p>This should return <code>7</> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script> <ins class="adsbygoogle" style="display:block" data-ad-client="ca-pub-5408099190056760" data-ad-slot="7305827575" data-ad-format="auto" data-full-width-responsive="true"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> </div> <div class="fly-panel detail-box" id="flyReply"> <fieldset class="layui-elem-field layui-field-title" style="text-align: center;"> <legend>4条回答</legend> </fieldset> <ul class="jieda" id="jieda"> <li data-id="111" class="jieda-daan"> <a name="item-1111111111"></a> <div class="detail-about detail-about-reply"> <a class="fly-avatar" href=""> <img src="https://www.e-learn.cn/qa/data/avatar/000/00/00/small_000000019.jpg" alt=" 野趣味 "> </a> <div class="fly-detail-user"> <a href="" class="fly-link"> <cite> 野趣味</cite> </a> <span>(楼主)</span> </div> <div class="detail-hits"> <span>2020-11-21 07:34</span> </div> </div> <div class="detail-body jieda-body photos"> <p> <p>If you don't have to support IE, you can use <code>selectionStart</code> and <code>selectionEnd</code> attributes of <code>textarea</code>.</p> <p>To get caret position just use <code>selectionStart</code>:</p> <pre><code>function getCaretPosition(textarea) { return textarea.selectionStart } </code></pre> <p>To get the strings surrounding the selection, use following code:</p> <pre><code>function getSurroundingSelection(textarea) { return [textarea.value.substring(0, textarea.selectionStart) ,textarea.value.substring(textarea.selectionStart, textarea.selectionEnd) ,textarea.value.substring(textarea.selectionEnd, textarea.value.length)] } </code></pre> <p>Demo on JSFiddle.</p> <p>See also HTMLTextAreaElement docs.</p> </p> <div class="appendcontent"> </div> </div> <div class="jieda-reply"> <span class="jieda-zan button_agree" type="zan" data-id='27939'> <i class="iconfont icon-zan"></i> <em>0</em> </span> <span type="reply" class="showpinglun" data-id="27939"> <i class="iconfont icon-svgmoban53"></i> 讨论(0) </span> <div class="jieda-admin"> </div> <div class="noreplaytext bb"> <center><div> <a href="https://www.e-learn.cn/qa/q-12153.html"> 查看其它4个回答 </a> </div></center> </div> </div> <div class="comments-mod " style="display: none; 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