function toThousandFilter(num) { return (+num || 0).toString().replace(/^-?\d+/g, m => m.replace(/(?=(?!\b)(\d{3})+$)/g, ',')) }
运行测试用例
function toThousandFilter(num) { return (+num || 0).toString().replace(/^-?\d+/g, m => m.replace(/(?=(?!\b)(\d{3})+$)/g, ',')) } toThousandFilter(100000000)
得到结果: