首页 > 解决方案 > JavaScript - updating value under certian conditions and append it to a <div></h1> <div id="body"><p>I have a pagaraph (<code>p</code>) appended to a <code>div</code>, that shows <code><t</p> </div> <div class="container" id="article"> <div class="page-header"> <h1>javascript - JavaScript - updating <textarea> value under certian conditions and append it to a <div></h1> <div id="body"><p>I have a pagaraph (<code>p</code>) appended to a <code>div</code>, that shows <code><t</h1> </div> <div class="con"> <h3>问题描述</h3> <p class="author">标签： <span>javascript</span><span>html</span><span>css</span></div> <h3>解决方案</h3> <hr> <div class="con "> <div class="body"> <p>听起来您只需要用以下内容替换<code>++</code>和换行符<code><br></code>：</p> <p></p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false"> <div class="snippet-code"> <pre class="snippet-code-js lang-js prettyprint-override"><code>var textarea = document.getElementById('textarea'); var textareaPreview = document.querySelector('.textarea-preview'); var currentText; textarea.onkeyup = function(){ currentText = textarea.value; var previewAsString = "<p class='p-preview'>" + currentText.replace(/\+\+|\n/g, '<br>') + "</p>" textareaPreview.innerHTML = previewAsString; };</code></pre> <pre class="snippet-code-css lang-css prettyprint-override"><code>textarea { width: 300px; height: 80px; resize: vertical; }</code></pre> <pre class="snippet-code-html lang-html prettyprint-override"><code><div class="block"> <textarea id="textarea" placeholder="Type here.."></textarea> </div> <div class="block"> <div class="textarea-preview"></div> </div></code></pre> </div> </div> <p></p> </div> <div class="clear"></div> </div> <hr> <h3>推荐阅读</h3> <ul> <li><a href="/question/55414902.html">javascript - Lodash过滤器功能不适用于正则表达式</a></li><li><a href="/question/55414904.html">django - 在不考虑模型的情况下生成 django 站点地图？</a></li><li><a href="/question/55414913.html">azure - Vbscript - OpenTextFile 在 Azure 中不起作用</a></li><li><a href="/question/55414914.html">java - JSP - 不能从不同的 JSP 页面调用 java 变量？</a></li><li><a href="/question/55414916.html">git - 如何避免“git gc”生成垃圾松散对象？</a></li><li><a href="/question/55414933.html">html - 如何在 html5 datepicker 中禁用日期数组列表</a></li><li><a href="/question/55414935.html">c# - 映射表达式</a></li><li><a href="/question/55414937.html">java - 预期总是 0 ，当使用 @Mock</a></li><li><a href="/question/55414938.html">javascript - 检查数组是否“包含”Javascript中的项目</a></li><li><a href="/question/55414939.html">javascript - 当我在输入文本中输入 @ 时，它应该在反应中以不同的颜色显示</a></li> </ul> </div> <footer> <p><a href="/">时间戳在线转换</a></p> </footer> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-6117966252207595" crossorigin="anonymous"></script> <script> var _hmt = _hmt || []; (function() { var hm = document.createElement("script"); hm.src = "https://hm.baidu.com/hm.js?7145e10314e5e27e886ad54be2aeb067"; var s = document.getElementsByTagName("script")[0]; s.parentNode.insertBefore(hm, s); })(); </script> </body></html>