http://www.w3school.com.cn/js...
获取当天的日期，一直减一去算就行了

可以把当前的时间转换为毫秒数减去七天的毫秒数再转换回来...

var today = new Date();

// 获取前七天的日期
var date1 = new Date(today.getTime() - (0 * 24 * 60 * 60 * 1000));
var date2 = new Date(today.getTime() - (1 * 24 * 60 * 60 * 1000));
var date3 = new Date(today.getTime() - (2 * 24 * 60 * 60 * 1000));
var date4 = new Date(today.getTime() - (3 * 24 * 60 * 60 * 1000));
var date5 = new Date(today.getTime() - (4 * 24 * 60 * 60 * 1000));
var date6 = new Date(today.getTime() - (5 * 24 * 60 * 60 * 1000));
var date7 = new Date(today.getTime() - (6 * 24 * 60 * 60 * 1000));

// 获取某天的年，月，日
var day = date1.getDate();
var month = date1.getMonth() + 1;
var year = date1.getFullYear();

<script>

var dayBefore=new Date().getTime()-24*60*60*7*1000;;
var result=new Date(dayBefore).getDate();
console.log(result);

</script>

http://www.cnblogs.com/leolov...
这个博客里面有些一个插件，获取前后7天的日期数据，形成日历