Js计算当前日，当前周开始结束时间，当前月份，当前年份

 <script type="text/javascript">
        //日期加上天数后的新日期.
        function GetDateStr(AddDayCount) {
            var dd = new Date();
            dd.setDate(dd.getDate()+ AddDayCount); //获取AddDayCount天后的日期
            var y = dd.getFullYear();
            var m = dd.getMonth() + 1; //获取当前月份的日期
            var d = dd.getDate();
            return y + "-" + m + "-" + d;
        }
        function bglxselect(obj) {
            var val = obj.value;
            var mydate = new Date();
            var datenow = mydate.getFullYear() + "-" + parseInt(mydate.getMonth() + 1) + "-" + mydate.getDate();
            var datemonth = mydate.getFullYear() + "-" + parseInt(mydate.getMonth() + 1) + "-01";
            var dateyear = mydate.getFullYear() + "-01-01";

            if (val == ‘day‘) {
                $("#rq1,#rq2").val(datenow)
            }
            if (val == ‘week‘) {
                var myday =parseInt(mydate.getDay());
                if (myday == 0) {
                    dateweek = GetDateStr(-6)
                }
                else {
                    myday = myday-1
                    dateweek = GetDateStr(-myday)

                }
                $("#rq1").val(dateweek);
                $("#rq2").val(datenow);
            }
            if (val == ‘month‘) {
                $("#rq1").val(datemonth);
                $("#rq2").val(datenow);
            }
            if (val == ‘year‘) {
                $("#rq1").val(dateyear);
                $("#rq2").val(datenow);
            }
            editform.action = "gzbg_tj.asp";
            editform.submit();
        }