注意：數字、空格以及標點符號為1個英文字元！漢字為2個字元！
推薦兩個線上網站：
站長工具-線上字數統計工具
良心網站-線上字數統計

<div class="column is-three-fifths-desktop is-narrow">
  <h1 class="title is-info is-4">線上字數統計</h1>
  <div class="field is-horizontal is-info">
    <div class="field-body is-info">
      <div class="field">
        <div class="control">
          <textarea class="textarea is-focused" placeholder="輸入(或貼上)統計字數的內容:" rows="12" id="content" autofocus=""></textarea>
        </div>
      </div>
    </div>
  </div>
  <div class="buttons is-right">
    <button class="button is-loading is-text is-small">Loading</button>
    <button class="button is-primary  is-rounded is-small" type="reset" value="reset" name="reset" onclick="resetForm()">全部清空!</button>
  </div>
  <div class="field is-grouped is-grouped-multiline" id="copyArea"> <span class="tag is-medium"> 共計： </span>
    <div class="control">
      <div class="tags has-addons"> <span class="tag is-dark is-medium" id="zishu">71</span> <span class="tag is-primary is-medium">個字數</span> </div>
    </div>
    <div class="control">
      <div class="tags has-addons"> <span class="tag is-dark is-medium" id="zifu">170</span> <span class="tag is-primary is-medium">個字元</span> </div>
    </div>
  </div>
  <div class="field is-grouped is-grouped-multiline"> <span class="tag"> 包含： </span>
    <div class="control">
      <div class="tags has-addons"> <span class="tag" id="hanzi">29</span> <span class="tag is-danger is-light">個漢字</span> </div>
    </div>
    <div class="control">
      <div class="tags has-addons"> <span class="tag" id="biaodian">6</span> <span class="tag is-info is-light">個標點(全形)</span> </div>
    </div>
    <div class="control">
      <div class="tags has-addons"> <span class="tag" id="zimu">58</span> <span class="tag is-success is-light">個字母</span> </div>
    </div>
    <div class="control">
      <div class="tags has-addons"> <span class="tag" id="shuzi">42</span> <span class="tag is-warning is-light">個數字</span> </div>
    </div>
  </div>
 

function CountChineseCharacters() {
        Words = $('content').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;
        for (i = 0; i < Words.length; i++) {
            var c = Words.charAt(i);
            if (c.match(/[\u4e00-\u9fa5]/)) {
                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++;
            }
        }
        $('hanzi').innerText = iTotal;
        $('zishu').innerText = inum + iTotal;
        $('biaodian').innerText = sTotal - iTotal;
        $('zimu').innerText = eTotal - inum;
        $('shuzi').innerText = inum;
        document.getElementById("zifu").innerHTML = iTotal * 2 + (sTotal - iTotal) * 2 + eTotal;
    }
 

JQuery 根據位元組數擷取字串（）

/*
 * 處理過長的字串，擷取並新增省略號
 * 注：半形長度為1，全形長度為2
 * 
 * pStr:字串
 * pLen:擷取長度
 * 
 * return: 擷取後的字串
 */
function autoAddEllipsis(pStr, pLen) {
 
	var _ret = cutString(pStr, pLen);
	var _cutFlag = _ret.cutflag;
	var _cutStringn = _ret.cutstring;
 
	if ("1" == _cutFlag) {
		return _cutStringn + "...";
	} else {
		return _cutStringn;
	}
}
 
/*
 * 取得指定長度的字串
 * 注：半形長度為1，全形長度為2
 * 
 * pStr:字串
 * pLen:擷取長度
 * 
 * return: 擷取後的字串
 */
function cutString(pStr, pLen) {
 
	// 原字串長度
	var _strLen = pStr.length;
 
	var _tmpCode;
 
	var _cutString;
 
	// 預設情況下，返回的字串是原字串的一部分
	var _cutFlag = "1";
 
	var _lenCount = 0;
 
	var _ret = false;
 
	if (_strLen <= pLen/2) {
		_cutString = pStr;
		_ret = true;
	}
 
	if (!_ret) {
		for (var i = 0; i < _strLen ; i++ ) {
			if (isFull(pStr.charAt(i))) {
				_lenCount += 2;
			} else {
				_lenCount += 1;
			}
 
			if (_lenCount > pLen) {
				_cutString = pStr.substring(0, i);
				_ret = true;
				break;
			} else if (_lenCount == pLen) {
				_cutString = pStr.substring(0, i + 1);
				_ret = true;
				break;
			}
		}
	}
	
	if (!_ret) {
		_cutString = pStr;
		_ret = true;
	}
 
	if (_cutString.length == _strLen) {
		_cutFlag = "0";
	}
 
	return {"cutstring":_cutString, "cutflag":_cutFlag};
}
 
/*
 * 判斷是否為全形
 * 
 * pChar:長度為1的字串
 * return: true:全形
 * 			false:半形
 */
function isFull (pChar) {
  if ((pChar.charCodeAt(0) > 128)) {
	return true;
    } else {
        return false;
    }
}