textarea 高度自适应

<div class="form-group">  
  <label class="col-sm-3 control-label"><span style="color: red">*</span>模板内容：</label>
  <div class="col-sm-8">
    <textarea id="content" rows="5" name="content" class="form-control" type="text" th:required="true" maxlength="1000"></textarea>
  </div>
</div>

$('#content').on('input', function(e) {
      $(e.target).css('height', 'auto').css('height', this.scrollHeight + 'px');
       //$(this).css('height', 'auto').css('height', this.scrollHeight + 'px');
  });