js对时间操作函数

自己写的：

/*

* 求某年某月的总天数

*/

function getDates(year, month) {

var now2 = new Date(year, month, 0); // 这是本月的最后一天

return now2.getDate();

}

/*

* 获取某年某月1号的星期序号

*/

function getFirstDay(year, month) {

var now = new Date(year, month - 1, 1);

var day = now.getDay();

if (day == 0)

return 7;

else {

return day;

}

}

/*

* 求某年某月星期的总数

*/

function getDays(year, month) {

if (getDates(year, month) - 28 +getFirstDay(year,month) >

return 6;

if (getDates(year, month) == 28

&& getFirstDay(year, month) == 1)

return 4;

else

return 5;

}

其他文章中转来的

1.<mce:script language=javascript><!--

2.//一天含 86,400,000 毫秒(24* 60 * 60*1000)

3.

4.//今天

5.function showToDay()

6.{

7.var Nowdate=new Date();

8.M=Number(Nowdate.getMonth())+1

9.return Nowdate.getYear()+"-"+M+"-"+Nowdate.getDate();

10.}

11.

12.//本周第一天

13.function showWeekFirstDay()

14.{

15.var Nowdate=new Date();

16.var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

17.return WeekFirstDay;

18.}

19.//本周最后一天

20.function showWeekLastDay()

21.{

22.var Nowdate=new Date();

23.var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

24.var WeekLastDay=new Date((WeekFirstDay/1000+6*86400)*1000);

25.return WeekLastDay;

26.}

27.

28.//本月第一天

29.function showMonthFirstDay()

30.{

31.var Nowdate=new Date();

32.var MonthFirstDay=new Date(Nowdate.getYear(),Nowdate.getMonth(),1);

33.return MonthFirstDay;

34.}

35.//本月最后一天

36.function showMonthLastDay()

37.{

38.var Nowdate=new Date();

39.var MonthNextFirstDay=new Date(Nowdate.getYear(),Nowdate.getMonth

40.

41.()+1,1);

42.var MonthLastDay=new Date(MonthNextFirstDay-86400000);

43.return MonthLastDay;

44.}

45.//上月第一天

46.function showPreviousFirstDay()

47.{

48.var MonthFirstDay=showMonthFirstDay()

49.return new Date(MonthFirstDay.getYear(),MonthFirstDay.getMonth()-

50.

51.1,1)

52.}

53.//上月最后一天

54.function showPreviousLastDay()

55.{

56.var MonthFirstDay=showMonthFirstDay();

57.return new Date(MonthFirstDay-86400000);

58.}

59.//上周第一天

60.function showPreviousFirstWeekDay()

61.{

62.var WeekFirstDay=showWeekFirstDay()

63.return new Date(WeekFirstDay-86400000*7)

64.}

65.//上周最后一天

66.function showPreviousLastWeekDay()

67.{

68.var WeekFirstDay=showWeekFirstDay()

69.return new Date(WeekFirstDay-86400000)

70.}

71.//上一天

72.function showPreviousDay()

73.{

74.var MonthFirstDay=new Date();

75.return new Date(MonthFirstDay-86400000);

76.}

77.//下一天

78.function showNextDay()

79.{

80.var MonthFirstDay=new Date();

81.return new Date((MonthFirstDay/1000+86400)*1000);

82.}

83.//下周第一天

84.function showNextFirstWeekDay()

85.{

86.var MonthFirstDay=showWeekLastDay()

87.return new Date((MonthFirstDay/1000+86400)*1000)

88.}

89.//下周最后一天

90.function showNextLastWeekDay()

91.{

92.var MonthFirstDay=showWeekLastDay()

93.return new Date((MonthFirstDay/1000+7*86400)*1000)

94.}

95.//下月第一天

96.function showNextFirstDay()

97.{

98.var MonthFirstDay=showMonthFirstDay()

99.return new Date(MonthFirstDay.getYear(),MonthFirstDay.getMonth()

100.

101.+1,1)

102.}

103.//下月最后一天

104.function showNextLastDay()

105.{

106.var MonthFirstDay=showMonthFirstDay()

107.return new Date(new Date(MonthFirstDay.getYear

108.

109.(),MonthFirstDay.getMonth()+2,1)-86400000)

110.}

111.function Date.prototype.toString(){

112.return this.getFullYear()+"-"+(this.getMonth()+1)+"-"+this.getDate

113.

114.();

115.}

116.function setDate(num){

117.if(num==1){

118.document.all.dateDate.value=showMonthFirstDay();

119.document.all.dateDate2.value=showMonthLastDay();

120.}

121.if(num==2){

122.document.all.dateDate.value=showWeekFirstDay();

123.document.all.dateDate2.value=showWeekLastDay();

124.}

125.if(num==3){

126.document.all.dateDate.value=showToDay();

127.document.all.dateDate2.value=showToDay();

128.}

129.if(num==4){

130.document.all.dateDate.value=showPreviousFirstDay();

131.document.all.dateDate2.value=showPreviousLastDay();

132.}

133.if(num==5){

134.document.all.dateDate.value=showNextFirstDay();

135.document.all.dateDate2.value=showNextLastDay();

136.}

137.if(num==6){

138.document.all.dateDate.value=showPreviousFirstWeekDay();

139.document.all.dateDate2.value=showPreviousLastWeekDay();

140.}

141.if(num==7){

142.document.all.dateDate.value=showNextFirstWeekDay();

143.document.all.dateDate2.value=showNextLastWeekDay();

144.}

145.if(num==8){

146.document.all.dateDate.value=showPreviousDay();

147.document.all.dateDate2.value=showPreviousDay();

148.}

149.if(num==9){

150.document.all.dateDate.value=showNextDay();

151.document.all.dateDate2.value=showNextDay();

152.}

153.}

154.

155.

// --></mce:script>

156.<input name=dateDate type=text>-><input name=dateDate2 type=text>

157. <input name=haha type=button value="上一月" onclick=setDate

158.

159.(4)>

160. <input name=haha type=button value="本月" onclick=setDate(1)

161.

162.>

163.<input name=haha type=button value="下一月" onclick=setDate(5)

164.

165.>

166.<input name=haha type=button value="上一周" onclick=setDate(6)

167.

168.>

169.<input name=haha type=button value="本周" onclick=setDate(2)>

170.<input name=haha type=button value="下一周" onclick=setDate(7)

171.

172.>

173.<input name=haha type=button value="上一天" onclick=setDate(8)

174.

175.>

176.<input name=haha type=button value="今天" onclick=setDate(3)>

177.<input name=haha type=button value="下一天" onclick=setDate(9)>