Question

我正在使用vb.net编写一个asp页面，我需要计算我的textarea中的字符数并显示消息：“X个字符剩余。”

这是我的asp代码：

  <td valign='top'>
                <textarea rows="5" id="content_txt" name="TextArea1" runat="server" maxlength="50"></textarea>
            </td>

Answer 1

这是JSFiddle

HTML：

<textarea rows="5" id="content_txt" name="TextArea1" runat="server" maxlength="50"></textarea>
<p id="message"></p>

JS：

var area = document.getElementById("content_txt");
var message = document.getElementById("message");
var maxLength = 50;
var checkLength = function() {
    if(area.value.length < maxLength) {
        message.innerHTML = (maxLength-area.value.length) + " characters remaining";
    }
}
setInterval(checkLength, 300);

Answer 2

我的朋友，我有一个小功能解决方案，试试这个：

HTML CODE

    <textarea name="message"placeholder="Reply message..." maxlength="155" onkeyup="counter(this);"></textarea>
<div id="counter_div">0/155</div>

JAVASCRIPT CODE

<script>
    function counter(msg){
        document.getElementById('counter_div').innerHTML = msg.value.length+'/155';
    }
</script>

此案例限制155个字符。

Answer 3

这会使用jquery var length = $('#content_txt').val().length;返回textarea的当前长度，其余的逻辑你必须试一试..

Answer 4

<td valign='top'>
  <textarea rows="5" id="content_txt" name="TextArea1" runat="server" maxlength="50"></textarea>
  <span id="character-count">100</span> characters remaining.
</td>


var totallength = 100;

$('textarea#input').on('keydown, keyup', function(e) {
     $('span#character-count').text((totallength - input.val().length));
});

Answer 5

试试这个

  function fix(dis)
    {
      var total=50; // ho many you want to show
      var val = dis.value;

      var count = val.length;
      document.getElementById('remaining').innerHTML= total-count;
    }

    <td valign='top'>
        <textarea rows="5" id="content_txt" name="TextArea1" runat="server" maxlength="50" onkeyup="fix(this)"></textarea>
    </td>

    <p><span id="remaining">0</span> Characters remaining</p>

Textarea计数字符验证

5 个答案: