```js var getWeek = function (year, month) { //1.根据年度和月份，创建日期 //应该先对year,month进行整数及范围校验的。 var d = new Date(); d.setYear(year); d.setMonth(month - 1); d.setDate(1); console.log(d); //获得周几 var weeks = ['周天', '周1', '周2', '周3', '周4', '周5', '周6']; return weeks[d.getDay()]; } alert(getWeek(2019, 2)); ```