php strtotime reverse | 易学教程

问题

Is there some function timetostr in php that will output today/tomorrow/next sunday/etc. from a given timestamp? So that timetostr(strtotime(x))=x

回答1:

This might be useful for people coming here.

/**
 * Format a timestamp to display its age (5 days ago, in 3 days, etc.).
 *
 * @param   int     $timestamp
 * @param   int     $now
 * @return  string
 */
function timetostr($timestamp, $now = null) {
    $age = ($now ?: time()) - $timestamp;
    $future = ($age < 0);
    $age = abs($age);

    $age = (int)($age / 60);        // minutes ago
    if ($age == 0) return $future ? "momentarily" : "just now";

    $scales = [
        ["minute", "minutes", 60],
        ["hour", "hours", 24],
        ["day", "days", 7],
        ["week", "weeks", 4.348214286],     // average with leap year every 4 years
        ["month", "months", 12],
        ["year", "years", 10],
        ["decade", "decades", 10],
        ["century", "centuries", 1000],
        ["millenium", "millenia", PHP_INT_MAX]
    ];

    foreach ($scales as list($singular, $plural, $factor)) {
        if ($age == 0)
            return $future
                ? "in less than 1 $singular"
                : "less than 1 $singular ago";
        if ($age == 1)
            return $future
                ? "in 1 $singular"
                : "1 $singular ago";
        if ($age < $factor)
            return $future
                ? "in $age $plural"
                : "$age $plural ago";
        $age = (int)($age / $factor);
    }
}

回答2:

There cannot be a strtotime reverse function because this is not a bijection. The source string from which you get a UNIX timestamp when you use strtotimecan be formatted in many different ways. So if you decide to reverse the function, how can you know what string format to use ? It could well be 2010-08-05 or 10 September 2000, etc. This is exactly why there is no reverse function, but as Andypandy rightly said, you have to use date()which allows you to actually define the string format you wish to end up with. I know this question is old, but I thought it deserved this answer so other users understand why there is no such function in PHP.

来源：https://stackoverflow.com/questions/8629788/php-strtotime-reverse

标签

php

strtotime