How to get current time in milliseconds in PHP?

问题

time() is in seconds - is there one in milliseconds?

回答1:

The short answer is:

$milliseconds = round(microtime(true) * 1000);

回答2:

Use microtime. This function returns a string separated by a space. The first part is the fractional part of seconds, the second part is the integral part. Pass in true to get as a number:

var_dump(microtime());       // string(21) "0.89115400 1283846202"
var_dump(microtime(true));   // float(1283846202.89)

Beware of precision loss if you use microtime(true).

There is also gettimeofday that returns the microseconds part as an integer.

var_dump(gettimeofday());
/*
array(4) {
  ["sec"]=>
  int(1283846202)
  ["usec"]=>
  int(891199)
  ["minuteswest"]=>
  int(-60)
  ["dsttime"]=>
  int(1)
}
*/

回答3:

As other have stated, you can use microtime() to get millisecond precision on timestamps.

From your comments, you seem to want it as a high-precision UNIX Timestamp. Something like DateTime.Now.Ticks in the .NET world.

You may use the following function to do so:

function millitime() {
  $microtime = microtime();
  $comps = explode(' ', $microtime);

  // Note: Using a string here to prevent loss of precision
  // in case of "overflow" (PHP converts it to a double)
  return sprintf('%d%03d', $comps[1], $comps[0] * 1000);
}

回答4:

Short answer:

64 bits platforms only!

function milliseconds() {
    $mt = explode(' ', microtime());
    return ((int)$mt[1]) * 1000 + ((int)round($mt[0] * 1000));
}

Long answer:

If you want an equilvalent function of time() in milliseconds first you have to consider that as time() returns the number of seconds elapsed since the "epoch time" (01/01/1970), the number of milliseconds since the "epoch time" is a big number and doesn't fit into a 32 bit integer.

The size of an integer in PHP can be 32 or 64 bit depending on platform.

From http://php.net/manual/en/language.types.integer.php

The size of an integer is platform-dependent, although a maximum value of about two billion is the usual value (that's 32 bits signed). 64-bit platforms usually have a maximum value of about 9E18, except for Windows, which is always 32 bit. PHP does not support unsigned integers. Integer size can be determined using the constant PHP_INT_SIZE, and maximum value using the constant PHP_INT_MAX since PHP 4.4.0 and PHP 5.0.5.

If you have 64 bit integers then you may use the following function:

function milliseconds() {
    $mt = explode(' ', microtime());
    return ((int)$mt[1]) * 1000 + ((int)round($mt[0] * 1000));
}

microtime() returns the number of seconds since the "epoch time" with precision up to microseconds with two numbers separated by space, like...

0.90441300 1409263371

The second number is the seconds (integer) preceeded by the decimal part.

The function milliseconds take the integer part multiplied by 1000

1409263371000

and adds the decimal part multiplied by 1000 and rounded to 0 decimals

1409263371904

Note that both $mt[1] and the result of round are casted to int. This is necessary because they are floats and the operation on them without casting would result in the function returning a float.

Finally, that function is slightly more precise than

round(microtime(true)*1000);

that with a ratio of 1:10 (approx.) returns 1 more millisecond than the correct result. This is due to the limited precision of the float type (microtime(true) returns a float). Anyway if you still prefer the shorter round(microtime(true)*1000); I would suggest casting to int the result.

Even if it's beyond the scope of the question it's worth mentioning that if your platform supports 64 bits integers then you can also get the current time in microseconds without incurring in overflow.

If fact 2^63 (approx. the biggest signed integer) divided by 10^6 * 3600 * 24 * 365 (approx. the microseconds in one year) gives approx. 292471.

That's the same value returned by echo PHP_INT_MAX / (1000000*3600*24*365);

In other words a signed integer have room to store a timespan of over 200000 years measured in microseconds.

You may have then

function microseconds() {
    $mt = explode(' ', microtime());
    return ((int)$mt[1]) * 1000000 + ((int)round($mt[0] * 1000000));
}

回答5:

Use microtime(true) in PHP 5, or the following modification in PHP 4:

array_sum(explode(' ', microtime()));

A portable way to write that code would be:

function getMicrotime()
{
    if (version_compare(PHP_VERSION, '5.0.0', '<'))
    {
        return array_sum(explode(' ', microtime()));
    }

    return microtime(true);
}

回答6:

echo date('Y-m-d H:i:s.') . gettimeofday()['usec'];

output:

2016-11-19 15:12:34.346351

回答7:

try this:

public function getTimeToMicroseconds() {
    $t = microtime(true);
    $micro = sprintf("%06d", ($t - floor($t)) * 1000000);
    $d = new DateTime(date('Y-m-d H:i:s.' . $micro, $t));

    return $d->format("Y-m-d H:i:s.u"); 
}

回答8:

$timeparts = explode(" ",microtime());
$currenttime = bcadd(($timeparts[0]*1000),bcmul($timeparts[1],1000));
echo $currenttime;

NOTE: PHP5 is required for this function due to the improvements with microtime() and the bc math module is also required (as we’re dealing with large numbers, you can check if you have the module in phpinfo).

Hope this help you.

回答9:

$the_date_time = new DateTime($date_string);
$the_date_time_in_ms = ($the_date_time->format('U') * 1000) +
    ($the_date_time->format('u') / 1000);

回答10:

This works even if you are on 32-bit PHP:

list($msec, $sec) = explode(' ', microtime());

$time_milli = $sec.substr($msec, 2, 3); // '1491536422147'
$time_micro = $sec.substr($msec, 2, 6); // '1491536422147300'

Note this doesn't give you integers, but strings. However this works fine in many cases, for example when building URLs for REST requests.

If you need integers, 64-bit PHP is mandatory.

Then you can reuse the above code and cast to (int):

list($msec, $sec) = explode(' ', microtime());

// these parentheses are mandatory otherwise the precedence is wrong!
//                  ↓                        ↓
$time_milli = (int) ($sec.substr($msec, 2, 3)); // 1491536422147
$time_micro = (int) ($sec.substr($msec, 2, 6)); // 1491536422147300

Or you can use the good ol' one-liners:

$time_milli = (int) round(microtime(true) * 1000);    // 1491536422147
$time_micro = (int) round(microtime(true) * 1000000); // 1491536422147300

回答11:

PHP 5.2.2 <

$d = new DateTime();
echo $d->format("Y-m-d H:i:s.u"); // u : Microseconds

PHP 7.0.0 <

$d = new DateTime();
echo $d->format("Y-m-d H:i:s.v"); // v : Milliseconds

回答12:

Use this:

function get_millis(){
  list($usec, $sec) = explode(' ', microtime());
  return (int) ((int) $sec * 1000 + ((float) $usec * 1000));
}

Bye

来源：https://stackoverflow.com/questions/3656713/how-to-get-current-time-in-milliseconds-in-php

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php

time

milliseconds