js时间基本操作

js 获取前一天的时
var today=new Date(); 
var yesterday_milliseconds=today.getTime()-1000*60*60*24; 
var yesterday=new Date();
 yesterday.setTime(yesterday_milliseconds);
 var strYear=yesterday.getFullYear(); 
 var strDay=yesterday.getDate(); 
 var strMonth=yesterday.getMonth()+1; 
 if(strMonth<10) { strMonth="0"+strMonth; }
 var strYesterday=strYear+"-"+strMonth+"-"+strDay; alert(strYesterday);

 Js获取当前日期时间及其它操作

 var myDate = new Date(); 
 //获取当前年份(2位) 
 myDate.getYear(); 
 //获取完整的年份(4位,1970-????) 
 myDate.getFullYear(); 
  //获取当前月份(0-11,0代表1月)
 myDate.getMonth(); 
//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.getDate(); 
 //获取当前时间(从1970.1.1开始的毫秒数) 
 myDate.getTime(); 
//获取当前小时数(0-23) 
 myDate.getHours(); 
  //获取当前分钟数(0-59) 
 myDate.getMinutes(); 
//获取当前秒数(0-59) 
 myDate.getSeconds(); 
 //获取当前毫秒数(0-999) 
 myDate.getMilliseconds(); 
 //获取当前日期 
 myDate.toLocaleDateString(); 
 //获取当前时间
 var mytime=myDate.toLocaleTimeString(); 
  //获取日期与时间
  myDate.toLocaleString( ); 

判断闰年 
 Date.prototype.isLeapYear = function()
 { return (0==this.getYear()%4&&((this.getYear()%100!=0)||(this.getYear()%400==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; } 
 //| 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> 
');
 document.write('myDate = Datue(''+month+'-'+day+'-'+year+'') 
');
 document.write('result = DatePart('ww', myDate) 
'); 
 document.write(' 
'); 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; } 
 若要显示:当前日期加时间(如:2009-06-12 12:00)
 function CurentTime() { 
 var now = new Date(); 
 var year = now.getFullYear();
 //年 var month = now.getMonth() + 1; 
 //月 var day = now.getDate(); //日 var hh = now.getHours(); //时
 var mm = now.getMinutes(); //分 
 var clock = year + "-"; 
 if(month < 10) clock += "0"; 
 clock += month + "-";
 if(day < 10) clock += "0"; 
 clock += day + " "; 
 if(hh < 10) clock += "0";
 clock += hh + ":"; 
 if (mm < 10) clock += '0'; 
 clock += mm; return(clock); }
【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/sily-boy/p/5703409.html