获取 JavaScript 的时间使用内置的 Date 函数完成

var mydate = new Date();

mydate.getYear(); //获取当前年份(2位)

mydate.getFullYear(); //获取完整的年份(4位,1970-????)

mydate.getMonth(); //获取当前月份(0-11,0代表1月)

mydate.getDate(); //获取当前日(1-31)

mydate.getDay(); //获取当前星期X(0-6,0代表星期天)

mydate.getTime(); //获取当前时间(从1970.1.1开始的毫秒数)

mydate.getHours(); //获取当前小时数(0-23)

mydate.getMinutes(); //获取当前分钟数(0-59)

mydate.getSeconds(); //获取当前秒数(0-59)

mydate.getMilliseconds(); //获取当前毫秒数(0-999)

mydate.toLocaleDateString(); //获取当前日期

var mytime=mydate.toLocaleTimeString(); //获取当前时间

mydate.toLocaleString( ); //获取日期与时间

日期时间脚本库方法列表

Date.prototype.isLeapYear 判断闰年

Date.prototype.Format 日期格式化

Date.prototype.DateAdd 日期计算

Date.prototype.DateDiff 比较日期差

Date.prototype.toString 日期转字符串

Date.prototype.toArray 日期分割为数组

Date.prototype.DatePart 取日期的部分信息

Date.prototype.MaxDayOfDate 取日期所在月的最大天数

Date.prototype.WeekNumOfYear 判断日期所在年的第几周

StringToDate 字符串转日期型

IsValidDate 验证日期有效性

CheckDateTime 完整日期时间检查

daysBetween 日期天数差

//---------------------------------------------------

// 判断闰年

//---------------------------------------------------

Date.prototype.isLeapYear = function () {
    return (0 == this.getYear() % 4 && ((this.getYear() != 0) || (this.getYear() == 0)));
}

//---------------------------------------------------

// 日期格式化

// 格式 YYYY/yyyy/YY/yy 表示年份

// MM/M 月份

// W/w 星期

// dd/DD/d/D 日期

// hh/HH/h/H 时间

// mm/m 分钟

// ss/SS/s/S 秒

//---------------------------------------------------

Date.prototype.Format = function (formatStr) {

    var str = formatStr;

    var Week = ['日', '一', '二', '三', '四', '五', '六'];

    str = str.replace(/yyyy|YYYY/, this.getFullYear());

    str = str.replace(/yy|YY/, (this.getYear() % 100) > 9 ? (this.getYear() % 100).toString() : '0' + (this.getYear() % 100));

    str = str.replace(/MM/, this.getMonth() > 9 ? this.getMonth().toString() : '0' + this.getMonth());

    str = str.replace(/M/g, this.getMonth());

    str = str.replace(/w|W/g, Week[this.getDay()]);

    str = str.replace(/dd|DD/, this.getDate() > 9 ? this.getDate().toString() : '0' + this.getDate());

    str = str.replace(/d|D/g, this.getDate());

    str = str.replace(/hh|HH/, this.getHours() > 9 ? this.getHours().toString() : '0' + this.getHours());

    str = str.replace(/h|H/g, this.getHours());

    str = str.replace(/mm/, this.getMinutes() > 9 ? this.getMinutes().toString() : '0' + this.getMinutes());

    str = str.replace(/m/g, this.getMinutes());

    str = str.replace(/ss|SS/, this.getSeconds() > 9 ? this.getSeconds().toString() : '0' + this.getSeconds());

    str = str.replace(/s|S/g, this.getSeconds());

    return str;

}

//+---------------------------------------------------

//| 求两个时间的天数差 日期格式为 YYYY-MM-dd

//+---------------------------------------------------

function daysBetween(DateOne, DateTwo) {

    var OneMonth = DateOne.substring(5, DateOne.lastIndexOf('-'));

    var OneDay = DateOne.substring(DateOne.length, DateOne.lastIndexOf('-') + 1);

    var OneYear = DateOne.substring(0, DateOne.indexOf('-'));


    var TwoMonth = DateTwo.substring(5, DateTwo.lastIndexOf('-'));

    var TwoDay = DateTwo.substring(DateTwo.length, DateTwo.lastIndexOf('-') + 1);

    var TwoYear = DateTwo.substring(0, DateTwo.indexOf('-'));


    var cha = ((Date.parse(OneMonth + '/' + OneDay + '/' + OneYear) - Date.parse(TwoMonth + '/' + TwoDay + '/' + TwoYear)) / 86400000);

    return Math.abs(cha);

}

//+---------------------------------------------------

//| 日期计算

//+---------------------------------------------------

Date.prototype.DateAdd = function (strInterval, Number) {

    var dtTmp = this;

    switch (strInterval) {

        case 's' :
            return new Date(Date.parse(dtTmp) + (1000 * Number));

        case 'n' :
            return new Date(Date.parse(dtTmp) + (60000 * Number));

        case 'h' :
            return new Date(Date.parse(dtTmp) + (3600000 * Number));

        case 'd' :
            return new Date(Date.parse(dtTmp) + (86400000 * Number));

        case 'w' :
            return new Date(Date.parse(dtTmp) + ((86400000 * 7) * Number));

        case 'q' :
            return new Date(dtTmp.getFullYear(), (dtTmp.getMonth()) + Number * 3, dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds());

        case 'm' :
            return new Date(dtTmp.getFullYear(), (dtTmp.getMonth()) + Number, dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds());

        case 'y' :
            return new Date((dtTmp.getFullYear() + Number), dtTmp.getMonth(), dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds());

    }

}

//+---------------------------------------------------

//| 比较日期差 dtEnd 格式为日期型或者 有效日期格式字符串

//+---------------------------------------------------

Date.prototype.DateDiff = function (strInterval, dtEnd) {

    var dtStart = this;

    if (typeof dtEnd == 'string')//如果是字符串转换为日期型
    {
        dtEnd = StringToDate(dtEnd);
    }

    switch (strInterval) {

        case 's' :
            return parseInt((dtEnd - dtStart) / 1000);

        case 'n' :
            return parseInt((dtEnd - dtStart) / 60000);

        case 'h' :
            return parseInt((dtEnd - dtStart) / 3600000);

        case 'd' :
            return parseInt((dtEnd - dtStart) / 86400000);

        case 'w' :
            return parseInt((dtEnd - dtStart) / (86400000 * 7));

        case 'm' :
            return (dtEnd.getMonth() + 1) + ((dtEnd.getFullYear() - dtStart.getFullYear()) * 12) - (dtStart.getMonth() + 1);

        case 'y' :
            return dtEnd.getFullYear() - dtStart.getFullYear();

    }

}

//+---------------------------------------------------

//| 日期输出字符串，重载了系统的toString方法

//+---------------------------------------------------

Date.prototype.toString = function (showWeek) {

    var myDate = this;

    var str = myDate.toLocaleDateString();

    if (showWeek) {
        var Week = ['日', '一', '二', '三', '四', '五', '六'];

        str += ' 星期' + Week[myDate.getDay()];
    }

    return str;

}

//+---------------------------------------------------

//| 日期合法性验证

//| 格式为：YYYY-MM-DD或YYYY/MM/DD

//+---------------------------------------------------

function IsValidDate(DateStr) {

    var sDate = DateStr.replace(/(^\s+|\s+$)/g, ''); //去两边空格;

    if (sDate == '') return true;

    //如果格式满足YYYY-(/)MM-(/)DD或YYYY-(/)M-(/)DD或YYYY-(/)M-(/)D或YYYY-(/)MM-(/)D就替换为''

    //数据库中，合法日期可以是:YYYY-MM/DD(2003-3/21),数据库会自动转换为YYYY-MM-DD格式

    var s = sDate.replace(/[\d]{ 4,4 }[\-/]{ 1 }[\d]{ 1,2 }[\-/]{ 1 }[\d]{ 1,2 }/g, '');

    if (s == '') //说明格式满足YYYY-MM-DD或YYYY-M-DD或YYYY-M-D或YYYY-MM-D
    {

        var t = new Date(sDate.replace(/\-/g, '/'));

        var ar = sDate.split(/[-/:]/);

        if (ar[0] != t.getYear() || ar[1] != t.getMonth() + 1 || ar[2] != t.getDate()) {

            //alert('错误的日期格式！格式为：YYYY-MM-DD或YYYY/MM/DD。注意闰年。');
            return false;
        }
    }

    else {
        //alert('错误的日期格式！格式为：YYYY-MM-DD或YYYY/MM/DD。注意闰年。');
        return false;
    }

    return true;

}

//+---------------------------------------------------

//| 日期时间检查

//| 格式为：YYYY-MM-DD HH:MM:SS

//+---------------------------------------------------

function CheckDateTime(str) {
    var reg = /^(\d+)-(\d{ 1,2 })-(\d{ 1,2 }) (\d{ 1,2 }):(\d{ 1,2 }):(\d{ 1,2 })$/;

    var r = str.match(reg);

    if (r == null)return false;

    r[2] = r[2] - 1;

    var d = new Date(r[1], r[2], r[3], r[4], r[5], r[6]);

    if (d.getFullYear() != r[1])return false;

    if (d.getMonth() != r[2])return false;

    if (d.getDate() != r[3])return false;

    if (d.getHours() != r[4])return false;

    if (d.getMinutes() != r[5])return false;

    if (d.getSeconds() != r[6])return false;

    return true;

}

//+---------------------------------------------------

//| 把日期分割成数组

//+---------------------------------------------------

Date.prototype.toArray = function () {

    var myDate = this;

    var myArray = Array();

    myArray[0] = myDate.getFullYear();

    myArray[1] = myDate.getMonth();

    myArray[2] = myDate.getDate();

    myArray[3] = myDate.getHours();

    myArray[4] = myDate.getMinutes();

    myArray[5] = myDate.getSeconds();

    return myArray;

}

//+---------------------------------------------------

//| 取得日期数据信息

//| 参数 interval 表示数据类型

//| y 年 m月 d日 w星期 ww周 h时 n分 s秒

//+---------------------------------------------------

Date.prototype.DatePart = function (interval) {

    var myDate = this;

    var partStr = '';

    var Week = ['日', '一', '二', '三', '四', '五', '六'];

    switch (interval) {

        case 'y' :
            partStr = myDate.getFullYear();
            break;

        case 'm' :
            partStr = myDate.getMonth() + 1;
            break;

        case 'd' :
            partStr = myDate.getDate();
            break;

        case 'w' :
            partStr = Week[myDate.getDay()];
            break;

        case 'ww' :
            partStr = myDate.WeekNumOfYear();
            break;

        case 'h' :
            partStr = myDate.getHours();
            break;

        case 'n' :
            partStr = myDate.getMinutes();
            break;

        case 's' :
            partStr = myDate.getSeconds();
            break;

    }

    return partStr;

}

//+---------------------------------------------------

//| 取得当前日期所在月的最大天数

//+---------------------------------------------------

Date.prototype.MaxDayOfDate = function () {

    var myDate = this;

    var ary = myDate.toArray();

    var date1 = (new Date(ary[0], ary[1] + 1, 1));

    var date2 = date1.dateAdd(1, 'm', 1);

    var result = dateDiff(date1.Format('yyyy-MM-dd'), date2.Format('yyyy-MM-dd'));

    return result;

}

//+---------------------------------------------------

//| 取得当前日期所在周是一年中的第几周

//+---------------------------------------------------

Date.prototype.WeekNumOfYear = function () {

    var myDate = this;

    var ary = myDate.toArray();

    var year = ary[0];

    var month = ary[1] + 1;

    var day = ary[2];

    document.write('< script language=VBScript\> \n');

    document.write('myDate = DateValue(""+month+" - "+day+" - "+year+"") \n');

    document.write('result = DatePart("ww", myDate) \n');

    document.write(' \n');

    return result;

}

//+---------------------------------------------------

//| 字符串转成日期类型

//| 格式 MM/dd/YYYY MM-dd-YYYY YYYY/MM/dd YYYY-MM-dd

//+---------------------------------------------------

function StringToDate(DateStr) {
    
    var converted = Date.parse(DateStr);

    var myDate = new Date(converted);

    if (isNaN(myDate)) {

        //var delimCahar = DateStr.indexOf('/')!=-1?'/':'-';

        var arys = DateStr.split('-');

        myDate = new Date(arys[0], --arys[1], arys[2]);

    }

    return myDate;

}