input、textArea实时显示剩余可输入的字数

<h2>实时显示剩余可输入的字数（字母，数字，中文都算一个字）</h2> <h>昵称:</h> <div> <input type="text" class="myText" onKeyUp="keypress(this)" /> <label class="name">15</label><span>/</span><label class="maxleng">15</label> </div> <h>评论内容:</h><br> <div> <textarea class="myText" style="width: 200px;height: 50px;" onKeyUp="keypress(this)" ></textarea> <label class="name">30</label><span>/</span><label class="maxleng">30</label> </div> <script type="text/javascript"> function keypress(t) { var txt=$(t).val().length; var len=$(t).parent().children('.maxleng').html()-txt; if(len>=0){ $(t).parent().children('.name').html(len); }else{ $(t).val($(t).val().substring(0,$(t).parent().children('.maxleng').text())); } } </script>