字符数计算，包含 CJK 字符

wordCount.js

var pattern = /[a-zA-Z0-9_\u0392-\u03c9\u00c0-\u00ff\u0600-\u06ff\u0400-\u04ff]+|[\u4e00-\u9fff\u3400-\u4dbf\uf900-\ufaff\u3040-\u309f\uac00-\ud7af]+/g;

function wordCount(str) {
  var m = str.match(pattern);
  var count = 0;
  if (!m) {
    return 0;
  }
  for (var i = 0; i < m.length; i++) {
    if (m[i].charCodeAt(0) >= 0x4e00) {
      count += m[i].length;
    } else {
      count += 1;
    }
  }
  return count;
};