js中常用的日期处理函数

/** 时间戳转字符串 */
function long2Str(time, format = 'yy-MM-dd HH:mm:ss') {if (!time || time <= 0) {return '';}var date = new Date(time);var year = date.getFullYear(),month = date.getMonth() + 1, //月份是从0开始 , 所以+1day = date.getDate(),hour = date.getHours(),min = date.getMinutes(),sec = date.getSeconds();var preArr = Array.apply(null, Array(10)).map(function (elem, index) {return '0' + index;}); //新建长度为10的数组 格式为 00 01 02 03var dateStr = format.replace(/yy/g, year).replace(/MM/g, preArr[month] || month).replace(/dd/g, preArr[day] || day).replace(/HH/g, preArr[hour] || hour).replace(/mm/g, preArr[min] || min).replace(/ss/g, preArr[sec] || sec);return dateStr;
}/** 日期转字符串 */
function date2Str(date, format = 'yyyy-MM-dd HH:mm:ss') {var o = {"M+": date.getMonth() + 1, //月"d+": date.getDate(), //天"H+": date.getHours(), //时(24小时制)"h+": date.getHours() % 12 == 0 ? date.getHours() : date.getHours() % 12, //时(12小时制)"m+": date.getMinutes(), //分"s+": date.getSeconds(), //秒"q+": Math.floor((date.getMonth() + 3) / 3), //季度"S": date.getMilliseconds() //毫秒}var week = {"0": "日","1": "一","2": "二","3": "三","4": "四","5": "五","6": "六"};if (/(y+)/.test(format)) {format = format.replace(RegExp.$1, (date.getFullYear() + "").substr(4 - RegExp.$1.length));}if (/(E+)/.test(format)) {format = format.replace(RegExp.$1, ((RegExp.$1.length > 1) ? (RegExp.$1.length > 2 ? "星期" : "周") : "") + week[date.getDay() + ""]);}for (var k in o) {if (new RegExp("(" + k + ")").test(format)) {format = format.replace(RegExp.$1, RegExp.$1.length == 1 ? o[k] : ("00" + o[k]).substr(("" + o[k]).length));}}return format;
}/** 日期字符串转时间戳(仅限yyyy-MM-dd hh:mm:ss 形式的字符串) */
function str2Long(dateStr){var date = new Date(Date.parse(date.replace(/-/g, "/")));return date.getTime();
}/** 日期字符串转Date (仅年月日) */
function str2Date(dateStr, separator = '-') {var dateArr = dateStr.split(separator);var year = parseInt(dateArr[0]);var month = dateArr[1].indexOf("0") == 0 ? parseInt(dateArr[1].substring(1)) : parseInt(dateArr[1]); //处理月份为04这样的情况var day = parseInt(dateArr[2]);return new Date(year, month - 1, day);
}/** sDateEnd - sDateStart 相差天数 */
function dateDiff(sDateStart, sDateEnd) { //sDateStart和sDateEnd是yyyy-MM-dd格式return parseInt((str2Date(sDateEnd) - str2Date(sDateStart)) / 86400000); //把相差的毫秒数转换为天数
}/** 判断是否是闰年 */
function isLeapYear(date) {var year = date.getYear();return year % 4 == 0 && year % 100 != 0 || year % 400 == 0;
}/*** @title 取得日期数据信息* @param  interval  表示数据类型 y:年 M:月 d:日 E:星期 h:时 m:分 s:秒*/
function getPart(date, interval) {var partStr = '';var Week = ['日', '一', '二', '三', '四', '五', '六'];switch (interval) {case 'y':partStr = date.getFullYear();break;case 'M':partStr = date.getMonth() + 1;break;case 'd':partStr = date.getDate();break;case 'E':partStr = Week[date.getDay()];break;case 'h':partStr = date.getHours();break;case 'm':partStr = myDate.getMinutes();break;case 's':partStr = date.getSeconds();break;}return partStr;
}