让我们做一些数学

You can use 7 alphanumeric digits. Each alphanumeric digit take a value from 36 possible different values (26 letters, 10 decimal digits) So we have 36^7 different values, that is 78364164096.

Now we compute the number of different values needed to represent a given timestamp in one year. To simplify things a bit we will allow some values that will never happen (ex: 31th november).

因此,我们已经

month: 12  -> coded from 0 to 11
day: 31  -> coded from 0 to 30
hour: 24
minute: 60
second: 60 

which gives use 32140800 different possibilites

We now divide 78364164096 / 32140800 which is ~2438, thus we will give an enumeration of timestamps from 00:00 jan 1 0000 to 23:59 dec 31 2437

当时编码正在编码。

X = second + minute*60 + hour*60*60 + 
    day*60*60*24 + month*60*60*24*31 + 
    year*60*60*24*31*12

而脱硫正在

second = X mod 60
minute = (X div 60) mod 60
hour = (X div 60*60) mod 24
day = (X div 60*60*24) mod 31
month = (X div 60*60*24*31) mod 12
year = X div 60*60*24*31*12

举一个例子:

Suppose you want to encode the date december 20, 1998, 05:33:12 So you would have

second: 12
minute: 33
hour: 5
day: 19   -> note that we encode days in the range 0..31
month: 11  -> note that we conde months in the range 0..11
year: 1998

因此,我们赞扬:

X = 12 + 33*60 + 5*60*60 + 
        19*60*60*24 + 11*60*60*24*31 + 
        1998*60*60*24*31*12

即X = 12 + 1980 + 18000 + 1641600 + 29462400 + 64217318400 = 64248442392

现在,我们就把它编码。

second = 64248442392 mod 60  = 12
minute = (64248442392 div 60) mod 60 = 33
hour = (64248442392 div 60*60) mod 24 = 5
day = (64248442392 div 60*60*24) mod 31 = 19
month = (64248442392 div 60*60*24*31) mod 12 = 11
year = 64248442392 div 60*60*24*31*12 = 1998

认为数字系统高于正数。 例如,hexa数字系统是16基数。 让我们在新的数字制度中说,我们有0-9位数、低位字母(a-z)和高位字母(A-Z)。 这使我们有62位可能的数位数,因此我们可以使用基数-62数字系统。 这里,有些Javascript代码用于转换——

function createConverter() {
    var charRange = (start, end) => Array.from(Array(end-start), 
                                         (v, i) => String.fromCharCode(i + start))

    var digits = charRange(48, 48+10)             // 0 to 9
                   .concat(charRange(97, 97+26))  // a to b
                   .concat(charRange(65, 65+26))  // A to B

    var base = digits.length

    return function(decimal) {
            var result = ""
            while (decimal >= base) {
                result = digits[decimal % base] + result
                decimal = parseInt(decimal / base)
            }
            result = digits[decimal] + result
            return result
        }
}

var convert = createConverter()
convert(parseInt(Date.now() / 1000)) // returns a 6-digit alphanumeric string 

<代码>charRange只是一种实用的arrow功能,从ASCII代码中产生一系列的特性。

<代码>数字代表我们计数系统的所有有效数字。 您可以在本清单中增加更有效的数字(如特别的斜体)。

<代码>为现有数位数(正数)

这个基数-62数字系统编码的输出数将超过1 700年,保持6位数。

EDIT: 实际日期.now()

我在给。