textarea字数限制输入字数，超字数时截取字符串显示-蒲公英云

textarea字数限制输入字数，超字数时截取字符串显示

标题textarea字数限制输入字数，超字数时截取字符串显示

// 超字数时截取字符串显示
  function calcNum(str, len) { 
    if (str.length <= len) { 
      return str;
    } else { 
      var value = str.substring(0, len);
      value = value.substring(0, value.length);
      return value;
    }
  }

在这里插入图片描述

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>计数限制-aixiaodou.cn</title>
    <style> .tips { height: 200px; overflow: auto; } </style>
</head>
<body>
<div>
    <textarea class="tips" wrap="virtual" id="tipsDesc" onkeypress="countNums()" onkeyup="countNums()" onblur="countNums();" placeholder="请将您的建议或遇到的问题告诉我们" onChange="countNums();"></textarea>
    <div class="nums"><span id="result">0</span>/500</div>
</div>
</body>
</html>
<script> function countNums() { var value = document.getElementById("tipsDesc").value; if (value.length >= 500) { document.getElementById("tipsDesc").value = value.substring(0, 500); } document.getElementById("result").innerHTML = document.getElementById("tipsDesc").value.length; } </script>