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

var date = new Date(year, month, day);

or

var date = new Date('01/01/1970');

格式为“01-01-1970”的日期字符串在FireFox中行不通,所以最好在日期格式字符串中使用“/”而不是“-”。

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)

还有另一种方式:

String.prototype.toDate = function(format) {
    format = format || "dmy";
    var separator = this.match(/[^0-9]/)[0];
    var components = this.split(separator);
    var day, month, year;
    for (var key in format) {
        var fmt_value = format[key];
        var value = components[key];
        switch (fmt_value) {
            case "d":
                day = parseInt(value);
                break;
            case "m":
                month = parseInt(value)-1;
                break;
            case "y":
                year = parseInt(value);
        }
    }
    return new Date(year, month, day);
};
a = "3/2/2017";
console.log(a.toDate("dmy"));
// Date 2017-02-03T00:00:00.000Z

只是新日期(st);

假设这是正确的格式。

转换为pt-BR格式:

    var dateString = "13/10/2014";
    var dataSplit = dateString.split('/');
    var dateConverted;

    if (dataSplit[2].split(" ").length > 1) {

        var hora = dataSplit[2].split(" ")[1].split(':');
        dataSplit[2] = dataSplit[2].split(" ")[0];
        dateConverted = new Date(dataSplit[2], dataSplit[1]-1, dataSplit[0], hora[0], hora[1]);

    } else {
        dateConverted = new Date(dataSplit[2], dataSplit[1] - 1, dataSplit[0]);
    }

我希望能帮助到别人!!

如果要从“dd/MM/yyyy”格式转换。这里有一个例子:

var pattern = /^(\d{1,2})\/(\d{1,2})\/(\d{4})$/;
var arrayDate = stringDate.match(pattern);
var dt = new Date(arrayDate[3], arrayDate[2] - 1, arrayDate[1]);

此解决方案适用于IE 9以下版本。