简单地使用这个:

var date = new Date('1970-01-01'); // Or your date here
console.log((date.getMonth() + 1) + '/' + date.getDate() + '/' +  date.getFullYear());

简单又甜蜜;)

format = function date2str(x, y) {
    var z = {
        M: x.getMonth() + 1,
        d: x.getDate(),
        h: x.getHours(),
        m: x.getMinutes(),
        s: x.getSeconds()
    };
    y = y.replace(/(M+|d+|h+|m+|s+)/g, function(v) {
        return ((v.length > 1 ? "0" : "") + z[v.slice(-1)]).slice(-2)
    });

    return y.replace(/(y+)/g, function(v) {
        return x.getFullYear().toString().slice(-v.length)
    });
}

结果:

format(new Date('Sun May 11,2014'), 'yyyy-MM-dd')
"2014-05-11

toISOString()假设日期是本地时间并将其转换为UTC。您将得到一个不正确的日期字符串。

下面的方法应该返回您需要的内容。

Date.prototype.yyyymmdd = function() {         

    var yyyy = this.getFullYear().toString();                                    
    var mm = (this.getMonth()+1).toString(); // getMonth() is zero-based         
    var dd  = this.getDate().toString();             

    return yyyy + '-' + (mm[1]?mm:"0"+mm[0]) + '-' + (dd[1]?dd:"0"+dd[0]);
};

来源:https://blog.justin.kelly.org.au/simple-javascript-function-to-format-the-date-as-yyyy-mm-dd/

只需利用内置的toISOString方法，将您的日期转换为ISO 8601格式:

let yourDate = new Date()
yourDate.toISOString().split('T')[0]

yourDate是你的日期对象。

编辑:@exbuddha在评论中写了这个来处理时区:

const offset = yourDate.getTimezoneOffset()
yourDate = new Date(yourDate.getTime() - (offset*60*1000))
return yourDate.toISOString().split('T')[0]

之前的一些答案是可以的，但是不是很灵活。我想要一些能够真正处理更多边缘情况的东西，所以我采用了@orangleliu的答案并扩展了它。https://jsfiddle.net/8904cmLd/1/

function DateToString(inDate, formatString) {
    // Written by m1m1k 2018-04-05

    // Validate that we're working with a date
    if(!isValidDate(inDate))
    {
        inDate = new Date(inDate);
    }

    // See the jsFiddle for extra code to be able to use DateToString('Sun May 11,2014', 'USA');
    //formatString = CountryCodeToDateFormat(formatString);

    var dateObject = {
        M: inDate.getMonth() + 1,
        d: inDate.getDate(),
        D: inDate.getDate(),
        h: inDate.getHours(),
        m: inDate.getMinutes(),
        s: inDate.getSeconds(),
        y: inDate.getFullYear(),
        Y: inDate.getFullYear()
    };

    // Build Regex Dynamically based on the list above.
    // It should end up with something like this: "/([Yy]+|M+|[Dd]+|h+|m+|s+)/g"
    var dateMatchRegex = joinObj(dateObject, "+|") + "+";
    var regEx = new RegExp(dateMatchRegex,"g");
    formatString = formatString.replace(regEx, function(formatToken) {
        var datePartValue = dateObject[formatToken.slice(-1)];
        var tokenLength = formatToken.length;

        // A conflict exists between specifying 'd' for no zero pad -> expand
        // to '10' and specifying yy for just two year digits '01' instead
        // of '2001'.  One expands, the other contracts.
        //
        // So Constrict Years but Expand All Else
        if (formatToken.indexOf('y') < 0 && formatToken.indexOf('Y') < 0)
        {
            // Expand single digit format token 'd' to
            // multi digit value '10' when needed
            var tokenLength = Math.max(formatToken.length, datePartValue.toString().length);
        }
        var zeroPad = (datePartValue.toString().length < formatToken.length ? "0".repeat(tokenLength) : "");
        return (zeroPad + datePartValue).slice(-tokenLength);
    });

    return formatString;
}

使用示例:

DateToString('Sun May 11,2014', 'MM/DD/yy');
DateToString('Sun May 11,2014', 'yyyy.MM.dd');
DateToString(new Date('Sun Dec 11,2014'),'yy-M-d');

formatDate(date) {
  const d = new Date(date)
  const ye = new Intl.DateTimeFormat('en', { year: 'numeric' }).format(d);
  const mo = new Intl.DateTimeFormat('en', { month: 'short' }).format(d);
  const da = new Intl.DateTimeFormat('en', { day: '2-digit' }).format(d);
  return `${da}-${mo}-${ye}`;
}

console.log("Formatated Date : ", formatDate("09/25/2020") )
// Output :: Formatated Date : 25-Sep-2020