菜鸟教程在线编辑器

 
                <!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>菜鸟教程(runoob.com)</title>
</head>
<body>

<p>点击按钮移除字符串的头尾空格。</p>

<button onclick="myFunction()">点我</button>

<script>
function myTrim(x) {
  return x.replace(/^\s+|\s+$/gm,'');
}

function myFunction() {
  var str = myTrim("    Runoob    ");
  alert(str);
}
</script>

</body>
</html>
              