利用JS實現點擊上一周或下一周卻換

1.頁面加載顯示當前年份的第幾周

?效果如圖：

html代碼：

? <font size="2" color="black">
?????<input id="btnweek5" type="button" class="btn" value="上周" οnclick="EduCommission.GetLastWeek()" />
??????<span id="year"></span><span>第</span><span id="week"></span><span>周</span>
????? <input id="btnweek6" type="button" value="下周" class="btn" οnclick="EduCommission.GetNextWeek()" />
??</font>

JS代碼：

??? var date = new Date();
??? nowyear = date.getFullYear();
??? nowweek = EduCommission.TheWeek(date);
??? $("#year").text(nowyear);
??? $("#week").text(nowweek - 1);

??

//本周 EduCommission.TheWeek = function (now) {

??? var totalDays = 0; ???

?? ?var years = now.getYear();

??? if (years < 1000) ?

?????? years += 1900; ??

? var days = new Array(12); ??

? ?days[0] = 31; ??

? ?days[2] = 31; ?

?? days[3] = 30; ?

?? days[4] = 31; ??

? ?days[5] = 30; ??

? ?days[6] = 31; ?

?? days[7] = 31; ?

?? days[8] = 30; ?

?? days[9] = 31; ?

?? days[10] = 30;

??? days[11] = 31;

??? if (Math.round(now.getYear() / 4) == now.getYear() / 4)

? ? { ?days[1] = 29; ??? }

? ? else { days[1] = 28;} ?

?? if (now.getMonth() == 0)

? ? ?{ ?

?????? totalDays = totalDays + now.getDate();?

? ? ?}

? else { ?

?????? var curMonth = now.getMonth();

? ? ? ?for (var count = 1; count <= curMonth; count++) { ?

? ? ? ?totalDays = totalDays + days[count - 1]; ??????? } ?

?????? totalDays = totalDays + now.getDate(); ??? } ???

? ? ? var week = Math.round(totalDays / 7) + 1; ???

? ? ? return week; }

?2.點擊上一周或下一周時：

//點擊上一周

EduCommission.GetLastWeek = function () {? ?

var y = $("#year").text();

??? var week = $("#week").text();

??? if (week == 1) {

??????? $("#year").text(y - 1);

??????? var strdate = y - 1 + "-12-31";

??????? var date = new Date(Date.parse(strdate.replace(/-/g, "/")));

??????? var lastyearweek = EduCommission.TheWeek(date);

??????? $("#week").text(lastyearweek); ??? } ???

? ?else { ???????

? ? ? $("#week").text(week - 1);

? ? ?} ?}；

//點擊下一周

EduCommission.GetNextWeek = function () {

??? var y = $("#year").text(); ?

? ? var week = $("#week").text();

??? if (y < nowyear) {

??????? var strdate = y + "-12-31";

??????? var date = new Date(Date.parse(strdate.replace(/-/g, "/")));? ? ? ? ? ? ??

? ? ? ? var weekcount = EduCommission.TheWeek(date);

??????? if (week == weekcount) {

??????????? $("#year").text(parseInt(y) + 1);

??????????? $("#week").text(1);

? ? ? ? ? ? }

? ? ? ?else {

??????????? $("#week").text(parseInt(week) + 1);??

? ? ? ? ? ? ?}

? ? ? else {

??????? $("#week").text(parseInt(week) + 1);

? ? ? ? ? ? }?

}；