jQuery實作還能輸入N字元

頁面：

<table cellpadding="0" cellspacing="0" border="0" width="100%">

                        <tr>

                            <td>

                                <textarea name="" id="doc" cols="30" rows="10"></textarea>

                            </td>

                        </tr>

                                <div class="face">

                                    <img src="/sitecn/images/face.jpg" /></div>

                                還能輸入<span id="count"></span>字

                                <input type="button" class="btn" value="提 交" />

                    </table>

JQuery:

<script type="text/javascript">

    var maxCount = 200;  // 最高字數，這個值可以自己配置

    $("#doc").keyup(function () {

        var len = getStrLength(this.value);

        var lenCount = maxCount - len; //計算還可以輸入多少個

        if (lenCount <0) {

            $(this).val($(this).val().substring(0, 200));

        }

        else {

            $("#count").html(lenCount);

    })

    // 中文字元判斷 

    function getStrLength(str) {

        var len = str.length;

        var reLen = 0;

        for (var i = 0; i < len; i++) {

            if (str.charCodeAt(i) < 27 || str.charCodeAt(i) > 126) {

                // 全角     

                reLen += 2;

            } else {

                reLen++;

            }

        return reLen;

    } 

</script>

本文轉自程式猿部落格51CTO部落格，原文連結http://blog.51cto.com/haihuiwei/1589960如需轉載請自行聯系原作者

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