如何将字符串转换为JavaScript日期对象?
var st = "date in some format"
var dt = new Date();
var dt_st = // st in Date format, same as dt.
如何将字符串转换为JavaScript日期对象?
var st = "date in some format"
var dt = new Date();
var dt_st = // st in Date format, same as dt.
当前回答
这个答案是基于卡塞姆的答案,但它也适用于两位数的年份。我对卡塞姆的答案进行了编辑,但以防它没有被批准,我还将这个作为单独的答案提交。
function stringToDate(_date,_format,_delimiter) {
var formatLowerCase=_format.toLowerCase();
var formatItems=formatLowerCase.split(_delimiter);
var dateItems=_date.split(_delimiter);
var monthIndex=formatItems.indexOf("mm");
var dayIndex=formatItems.indexOf("dd");
var yearIndex=formatItems.indexOf("yyyy");
var year = parseInt(dateItems[yearIndex]);
// adjust for 2 digit year
if (year < 100) { year += 2000; }
var month=parseInt(dateItems[monthIndex]);
month-=1;
var formatedDate = new Date(year,month,dateItems[dayIndex]);
return formatedDate;
}
stringToDate("17/9/14","dd/MM/yyyy","/");
stringToDate("17/9/2014","dd/MM/yyyy","/");
stringToDate("9/17/2014","mm/dd/yyyy","/")
stringToDate("9-17-2014","mm-dd-yyyy","-")
其他回答
我已经创建了parseDateTime函数将字符串转换为日期对象,它在所有浏览器(包括IE浏览器)中工作,检查是否有人需要,引用 https://github.com/Umesh-Markande/Parse-String-to-Date-in-all-browser
function parseDateTime(datetime) {
var monthNames = [
"January", "February", "March",
"April", "May", "June", "July",
"August", "September", "October",
"November", "December"
];
if(datetime.split(' ').length == 3){
var date = datetime.split(' ')[0];
var time = datetime.split(' ')[1].replace('.00','');
var timearray = time.split(':');
var hours = parseInt(time.split(':')[0]);
var format = datetime.split(' ')[2];
var bits = date.split(/\D/);
date = new Date(bits[0], --bits[1], bits[2]); /* if you change format of datetime which is passed to this function, you need to change bits e.x ( bits[0], bits[1], bits[2 ]) position as per date, months and year it represent bits array.*/
var day = date.getDate();
var monthIndex = date.getMonth();
var year = date.getFullYear();
if ((format === 'PM' || format === 'pm') && hours !== 12) {
hours += 12;
try{ time = hours+':'+timearray[1]+':'+timearray[2] }catch(e){ time = hours+':'+timearray[1] }
}
var formateddatetime = new Date(monthNames[monthIndex] + ' ' + day + ' ' + year + ' ' + time);
return formateddatetime;
}else if(datetime.split(' ').length == 2){
var date = datetime.split(' ')[0];
var time = datetime.split(' ')[1];
var bits = date.split(/\D/);
var datetimevalue = new Date(bits[0], --bits[1], bits[2]); /* if you change format of datetime which is passed to this function, you need to change bits e.x ( bits[0], bits[1], bits[2 ]) position as per date, months and year it represent bits array.*/
var day = datetimevalue.getDate();
var monthIndex = datetimevalue.getMonth();
var year = datetimevalue.getFullYear();
var formateddatetime = new Date(monthNames[monthIndex] + ' ' + day + ' ' + year + ' ' + time);
return formateddatetime;
}else if(datetime != ''){
var bits = datetime.split(/\D/);
var date = new Date(bits[0], --bits[1], bits[2]); /* if you change format of datetime which is passed to this function, you need to change bits e.x ( bits[0], bits[1], bits[2 ]) position as per date, months and year it represent bits array.*/
return date;
}
return datetime;
}
var date1 = '2018-05-14 05:04:22 AM'; // yyyy-mm-dd hh:mm:ss A
var date2 = '2018/05/14 05:04:22 AM'; // yyyy/mm/dd hh:mm:ss A
var date3 = '2018/05/04'; // yyyy/mm/dd
var date4 = '2018-05-04'; // yyyy-mm-dd
var date5 = '2018-05-14 15:04:22'; // yyyy-mm-dd HH:mm:ss
var date6 = '2018/05/14 14:04:22'; // yyyy/mm/dd HH:mm:ss
console.log(parseDateTime(date1))
console.log(parseDateTime(date2))
console.log(parseDateTime(date3))
console.log(parseDateTime(date4))
console.log(parseDateTime(date5))
console.log(parseDateTime(date6))
**Output---**
Mon May 14 2018 05:04:22 GMT+0530 (India Standard Time)
Mon May 14 2018 05:04:22 GMT+0530 (India Standard Time)
Fri May 04 2018 00:00:00 GMT+0530 (India Standard Time)
Fri May 04 2018 00:00:00 GMT+0530 (India Standard Time)
Mon May 14 2018 15:04:22 GMT+0530 (India Standard Time)
Mon May 14 2018 14:04:22 GMT+0530 (India Standard Time)
只是新日期(st);
假设这是正确的格式。
字符串解析的最佳字符串格式是ISO日期格式和JavaScript date对象构造函数。
ISO格式的例子:YYYY-MM-DD或YYYY-MM-DDTHH:MM:SS。
但是等等!仅仅使用“ISO格式”本身并不能可靠地工作。字符串有时解析为UTC,有时解析为localtime(基于浏览器供应商和版本)。最佳实践应该始终是将日期存储为UTC,并以UTC进行计算。
要将日期解析为UTC,请添加Z -例如:new date ('2011-04-11T10:20:30Z')。
使用.toUTCString()显示UTC日期, 使用. tostring()以用户的本地时间显示日期。
关于MDN |日期和这个答案的更多信息。
对于旧的Internet Explorer兼容性(小于9的IE版本在日期构造函数中不支持ISO格式),您应该将日期时间字符串表示拆分为部分,然后您可以使用使用日期时间部分的构造函数,例如:new Date('2011', '04' - 1, '11', '11', '51', '00')。注意,月份的数字必须小于1。
替代方法-使用适当的库:
您还可以利用Moment.js库,该库允许使用指定的时区解析日期。
对于那些正在寻找小巧而智能的解决方案的人:
String.prototype.toDate = function(format)
{
var normalized = this.replace(/[^a-zA-Z0-9]/g, '-');
var normalizedFormat= format.toLowerCase().replace(/[^a-zA-Z0-9]/g, '-');
var formatItems = normalizedFormat.split('-');
var dateItems = normalized.split('-');
var monthIndex = formatItems.indexOf("mm");
var dayIndex = formatItems.indexOf("dd");
var yearIndex = formatItems.indexOf("yyyy");
var hourIndex = formatItems.indexOf("hh");
var minutesIndex = formatItems.indexOf("ii");
var secondsIndex = formatItems.indexOf("ss");
var today = new Date();
var year = yearIndex>-1 ? dateItems[yearIndex] : today.getFullYear();
var month = monthIndex>-1 ? dateItems[monthIndex]-1 : today.getMonth()-1;
var day = dayIndex>-1 ? dateItems[dayIndex] : today.getDate();
var hour = hourIndex>-1 ? dateItems[hourIndex] : today.getHours();
var minute = minutesIndex>-1 ? dateItems[minutesIndex] : today.getMinutes();
var second = secondsIndex>-1 ? dateItems[secondsIndex] : today.getSeconds();
return new Date(year,month,day,hour,minute,second);
};
例子:
"22/03/2016 14:03:01".toDate("dd/mm/yyyy hh:ii:ss");
"2016-03-29 18:30:00".toDate("yyyy-mm-dd hh:ii:ss");
var st = "26.04.2013";
var pattern = /(\d{2})\.(\d{2})\.(\d{4})/;
var dt = new Date(st.replace(pattern,'$3-$2-$1'));
输出将是:
dt => Date {Fri Apr 26 2013}