在主题functions.php文件中加入下面的代码即可，实际就是调用插件接口向文章编辑器页面插入css和js来实现的。

Typecho_Plugin::factory('admin/write-post.php')->bottom = array('myyodu', 'one');
Typecho_Plugin::factory('admin/write-page.php')->bottom = array('myyodu', 'one');
class myyodu {
    public static function one()
    {
    ?>
<style>
.field.is-grouped{display:-webkit-box;display:-ms-flexbox;display:flex;-webkit-box-pack:start;-ms-flex-pack:start;justify-content:flex-start;  -ms-flex-wrap: wrap;flex-wrap: wrap;}.field.is-grouped>.control{-ms-flex-negative:0;flex-shrink:0}.field.is-grouped>.control:not(:last-child){margin-bottom:.5rem;margin-right:.75rem}.field.is-grouped>.control.is-expanded{-webkit-box-flex:1;-ms-flex-positive:1;flex-grow:1;-ms-flex-negative:1;flex-shrink:1}.field.is-grouped.is-grouped-centered{-webkit-box-pack:center;-ms-flex-pack:center;justify-content:center}.field.is-grouped.is-grouped-right{-webkit-box-pack:end;-ms-flex-pack:end;justify-content:flex-end}.field.is-grouped.is-grouped-multiline{-ms-flex-wrap:wrap;flex-wrap:wrap}.field.is-grouped.is-grouped-multiline>.control:last-child,.field.is-grouped.is-grouped-multiline>.control:not(:last-child){margin-bottom:.75rem}.field.is-grouped.is-grouped-multiline:last-child{margin-bottom:-.75rem}.field.is-grouped.is-grouped-multiline:not(:last-child){margin-bottom:0}.tags{-webkit-box-align:center;-ms-flex-align:center;align-items:center;display:-webkit-box;display:-ms-flexbox;display:flex;-ms-flex-wrap:wrap;flex-wrap:wrap;-webkit-box-pack:start;-ms-flex-pack:start;justify-content:flex-start}.tags .tag{margin-bottom:.5rem}.tags .tag:not(:last-child){margin-right:.5rem}.tags:last-child{margin-bottom:-.5rem}.tags:not(:last-child){margin-bottom:1rem}.tags.has-addons .tag{margin-right:0}.tags.has-addons .tag:not(:first-child){border-bottom-left-radius:0;border-top-left-radius:0}.tags.has-addons .tag:not(:last-child){border-bottom-right-radius:0;border-top-right-radius:0}.tag{-webkit-box-align:center;-ms-flex-align:center;align-items:center;background-color:#f5f5f5;border-radius:3px;color:#4a4a4a;display:-webkit-inline-box;display:-ms-inline-flexbox;display:inline-flex;font-size:.75rem;height:2em;-webkit-box-pack:center;-ms-flex-pack:center;justify-content:center;line-height:1.5;padding-left:.75em;padding-right:.75em;white-space:nowrap}.tag .delete{margin-left:.25em;margin-right:-.375em}.tag.is-white{background-color:#fff;color:#0a0a0a}.tag.is-black{background-color:#0a0a0a;color:#fff}.tag.is-light{background-color:#fff;color:#363636}.tag.is-dark{background-color:#363636;color:#f5f5f5}.tag.is-primary{background-color:#00d1b2;color:#fff}.tag.is-info{background-color:#3273dc;color:#fff}.tag.is-success{background-color:#23d160;color:#fff}.tag.is-warning{background-color:#ffdd57;color:rgba(0,0,0,.7)}.tag.is-danger{background-color:#ff3860;color:#fff}.tag.is-large{font-size:1.25rem}.tag.is-delete{margin-left:1px;padding:0;position:relative;width:2em}.tag.is-delete:after,.tag.is-delete:before{background-color:currentColor;content:"";display:block;left:50%;position:absolute;top:50%;-webkit-transform:translateX(-50%) translateY(-50%) rotate(45deg);transform:translateX(-50%) translateY(-50%) rotate(45deg);-webkit-transform-origin:center center;transform-origin:center center}.tag.is-delete:before{height:1px;width:50%}.tag.is-delete:after{height:50%;width:1px}.tag.is-delete:focus,.tag.is-delete:hover{background-color:#e8e8e8}.tag.is-delete:active{background-color:#dbdbdb}.tag.is-rounded{border-radius:290486px}
</style>
<script language="javascript">
    var EventUtil = function() {};
    EventUtil.addEventHandler = function(obj, EventType, Handler) {
        if (obj.addEventListener) {
            obj.addEventListener(EventType, Handler, false);
        }
        else if (obj.attachEvent) {
            obj.attachEvent('on' + EventType, Handler);
        } else {
            obj['on' + EventType] = Handler;
        }
    }
    if (document.getElementById("text")) {
        EventUtil.addEventHandler(document.getElementById('text'), 'propertychange', CountChineseCharacters);
        EventUtil.addEventHandler(document.getElementById('text'), 'input', CountChineseCharacters);
    }
    function showit(Word) {
        alert(Word);
    }
    function CountChineseCharacters() {
        Words = document.getElementById('text').value;
        var W = new Object();
        var Result = new Array();
        var iNumwords = 0;
        var sNumwords = 0;
        var sTotal = 0;
        var iTotal = 0;
        var eTotal = 0;
        var otherTotal = 0;
        var bTotal = 0;
        var inum = 0;
      var znum = 0;
      var gl = 0;
      var paichu = 0;
        for (i = 0; i < Words.length; i++) {
            var c = Words.charAt(i);
            if (c.match(/[\u4e00-\u9fa5]/) || c.match(/[\u0800-\u4e00]/) || c.match(/[\uac00-\ud7ff]/)) {
                if (isNaN(W[c])) {
                    iNumwords++;
                    W[c] = 1;
                }
                iTotal++;
            }
        }
        for (i = 0; i < Words.length; i++) {
            var c = Words.charAt(i);
            if (c.match(/[^\x00-\xff]/)) {
                if (isNaN(W[c])) {
                    sNumwords++;
                }
                sTotal++;
            } else {
                eTotal++;
            }
            if (c.match(/[0-9]/)) {
                inum++;
            }
           if (c.match(/[a-zA-Z]/)) {
                znum++;
            }
          if (c.match(/[\s]/)) {
               gl++;
            }
           if (c.match(/[　◕‿↑↓←→↖↗↘↙↔↕。《》、【】“”•‘’❝❞′……—―‐〈〉„╗╚┐└‖〃「」‹›『』〖〗〔〕∶〝〞″≌∽≦≧≒≠≤≥㏒≡≈✓✔◐◑◐◑✕✖★☆₸₹€₴₰₤₳र₨₲₪₵₣₱฿₡₮₭₩₢₧₥₫₦₠₯○㏄㎏㎎㏎㎞㎜㎝㏕㎡‰〒々℃℉ㄅㄆㄇㄈㄉㄊㄋㄌㄍㄎㄏㄐㄑㄒㄓㄔㄕㄖㄗㄘㄙㄚㄛㄜㄝㄞㄟㄠㄡㄢㄣㄤㄥㄦㄧㄨㄩ]/)) {
               paichu++;
            }
        }
        document.getElementById('hanzi').innerText = iTotal - paichu;
        document.getElementById('zishu').innerText = inum + iTotal - paichu;
        document.getElementById('biaodian').innerText = sTotal - iTotal + eTotal - inum - znum - gl + paichu;
        document.getElementById('zimu').innerText = znum;
        document.getElementById('shuzi').innerText = inum;
        document.getElementById("zifu").innerHTML = iTotal * 2 + (sTotal - iTotal) * 2 + eTotal;
    }
</script>
<script> 
$(document).ready(function(){
$("#wmd-editarea").append('<div class="field is-grouped"><span class="tag">共计：</span><div class="control"><div class="tags has-addons"><span class="tag is-dark" id="zishu">0</span> <span class="tag is-primary">个字数</span></div></div><div class="control"><div class="tags has-addons"><span class="tag is-dark" id="zifu">0</span> <span class="tag is-primary">个字符</span></div></div><span class="tag">包含：</span><div class="control"><div class="tags has-addons"><span class="tag is-light" id="hanzi">0</span> <span class="tag is-danger">个文字</span></div></div><div class="control"><div class="tags has-addons"><span class="tag is-light" id="biaodian">0</span> <span class="tag is-info">个符号</span></div></div><div class="control"><div class="tags has-addons"><span class="tag is-light" id="zimu">0</span> <span class="tag is-success">个字母</span></div></div><div class="control"><div class="tags has-addons"><span class="tag is-light" id="shuzi">0</span> <span class="tag is-warning">个数字</span></div></div></div>');
CountChineseCharacters();
});
</script>
<?php
    }
}

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