驼峰名转下划线：‘componentMapModelRegistry’.match(/^[a-z][a-z0-9]+|[A-Z][a-z0-9]*/g).join(’’).toLowerCase(); // component_map_model_registry获取URL参数function wordCount(data) { var pattern = /[a-zA-Z0-9\u0392-\u03c9]+|[\u4E00-\u9FFF\u3400-\u4dbf\uf900-\ufaff\u3040-\u309f\uac00-\ud7af]+/g; var m = data.match(pattern); var count = 0; if( m === null ) return count; for (var i = 0; i < m.length; i++) { if (m[i].charCodeAt(0) >= 0x4E00) { count += m[i].length; } else { count += 1; } } return count;}var text = ‘贷款买房，也意味着你能给自己的资产加杠杆，能够撬动更多的钱，来孳生更多的财务性收入。’;wordCount(text); // 38特殊字符转义function htmlspecialchars (str) { var str = str.toString().replace(/&/g, “&”).replace(/</g, “<”).replace(/>/g, “>”).replace(/"/g, ‘"’); return str;}htmlspecialchars(’&jfkds<>’); // “&jfkds<>“格式化数量// 方法一function formatNum (num, n) { if (typeof num == “number”) { num = String(num.toFixed(n || 0)); var re = /(-?\d+)(\d{3})/; while (re.test(num)) num = num.replace(re, “$1,$2”); return num; } return num;}formatNum(2313123, 3); // “2,313,123.000”// 方法二'2313123’.replace(/\B(?=(\d{3})+(?!\d))/g, ‘,’); // “2,313,123”// 方法三function formatNum(str) { return str.split(’’).reverse().reduce((prev, next, index) => { return ((index % 3) ? next : (next + ‘,’)) + prev });}测试质数var arr = ‘abcdaabc’;var info = arr .split(’’) .reduce((p, k) => (p[k]++ || (p[k] = 1), p), {});console.log(info); //{ a: 3, b: 2, c: 2, d: 1 }如何优雅的实现金钱格式化：1234567890 –> 1,234,567,890var test1 = ‘1234567890’var format = test1.replace(/\B(?=(\d{3})+(?!\d))/g, ‘,’)console.log(format) // 1,234,567,890代码来自于收集，方便学习