cuing · December 11, 2013 02:55
diff --git a/jsbin.urETIyIT.css b/jsbin.urETIyIT.css
 #autoresize {
  resize: none;
  outline: none;
  width: 300px;
  word-break: break-all;
  font-family:sans-serif;
  font-size: 1em;
  line-height: 1.2em;
  margin: 0px;
 }

 #hiddenDiv {
  width: 300px;
  word-break: break-all;
    line-height: 1.2em;
  min-height: 1.2em;
  font-family:sans-serif;
  font-size: 1em;
  display: none;
 }

diff --git a/jsbin.urETIyIT.html b/jsbin.urETIyIT.html
 <!DOCTYPE html>
 <html>
 <head>
 <script src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.2/jquery.min.js"></script>
 <meta charset=utf-8 />
 <title>textarea auto height</title>
 </head>
 <body>
  <textarea id="autoresize" rows="1"></textarea>
  <div id="hiddenDiv"></div>
 </body>
 </html>
diff --git a/jsbin.urETIyIT.js b/jsbin.urETIyIT.js
 var obj = $('#autoresize');
 var hidden = $('#hiddenDiv');

 function autoHeight() {
  console.log(obj.value);
  hidden.style.height = obj.offsetHeight;    
 }
 
 obj.keyup(function() {
    var txt = obj.val();
    hidden.text(txt);
    obj.css('height', hidden.height());
 });
	<!DOCTYPE html>
	<html>
	<head>
	<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.2/jquery.min.js"></script>
	<meta charset=utf-8 />
	<title>textarea auto height</title>
	</head>
	<body>
	<textarea id="autoresize" rows="1"></textarea>
	<div id="hiddenDiv"></div>
	</body>
	</html>
	var obj = $('#autoresize');
	var hidden = $('#hiddenDiv');

	function autoHeight() {
	console.log(obj.value);
	hidden.style.height = obj.offsetHeight;
	}

	obj.keyup(function() {
	var txt = obj.val();
	hidden.text(txt);
	obj.css('height', hidden.height());
	});