js设置本周 本月 本年

var SetSearchDate = function (sign, sid, eid) {//sign 标识符区分本周本月本年，sid开始时间id，eid结束时间id
var now = new Date();
var nowDayOfWeek = now.getDay(); //今天本周的第几天
var nowMonth = now.getMonth() + 1; //当前月
var nowYear = now.getFullYear(); //当前年 if (sign == 1)//本周
{
var first_milliseconds = new Date().getTime() - 1000 * 60 * 60 * 24 * (nowDayOfWeek - 1);
var last_milliseconds = first_milliseconds + 1000 * 60 * 60 * 24 * 6;
$("#" + sid).val(formatDate(new Date(first_milliseconds)));
$("#" + eid).val(formatDate(new Date(last_milliseconds)));
} else if (sign == 2)//本月
{
var firstdate = nowYear + '-' + nowMonth + '-01';
var lastdate = nowYear + '-' + nowMonth + '-' + new Date(nowYear, nowMonth, 0).getDate();
$("#" + sid).val(firstdate);
$("#" + eid).val(lastdate);
} else if (sign == 3)//本年
{
$("#" + sid).val(nowYear + '-01' + '-01');
$("#" + eid).val(nowYear + '-12' + '-31');
}
}