PHP 8.4 introduces two convenient methods for handling microseconds in DateTime objects: getMicrosecond() and setMicrosecond().

Before PHP 8.4, working with microseconds was clunky. You had to extract values using string formatting or reset the entire time:

<?php

// Old way - getting microseconds
$date = new DateTimeImmutable();
$microseconds = (int) $date->format('u');
echo $microseconds.PHP_EOL;

// Old way - setting microseconds (very verbose)
$date = $date->setTime(
    (int) $date->format('G'), // hour
    (int) $date->format('i'), // minute
    (int) $date->format('s'), // second
    628115, // microsecond
);
$microseconds = (int) $date->format('u');
echo $microseconds.PHP_EOL;

PHP 8.4 simplifies this with dedicated methods:

<?php

// Get microseconds
$date = new DateTimeImmutable();
$microseconds = $date->getMicrosecond();
echo $microseconds; // Outputs a value between 0-999999

// Set microseconds
$date = new DateTime();
$date->setMicrosecond(628115);
$microseconds = $date->getMicrosecond();
echo $microseconds.PHP_EOL; // 628115

When setting microseconds, values must be between 0 and 999999. Anything outside this range throws a DateRangeError:

try {
    $date->setMicrosecond(1000000); // Too large
} catch (DateRangeError $e) {
    echo $e->getMessage();
    // DateTime::setMicrosecond(): Argument #1 ($microsecond)
    // must be between 0 and 999999, 1000000 given
}

Microseconds are perfect for high-precision timing, like measuring function execution time:

<?php

// Start time
$start = new DateTime();

// Run some process
array_fill(0, 1000000, 'test');

// End time
$end = new DateTime();

// Calculate difference
$startMicro = $start->getMicrosecond();
$endMicro = $end->getMicrosecond();
$microDiff = $endMicro - $startMicro;

echo "Process took approximately $microDiff microseconds";

These new methods make working with high-precision timestamps much simpler and more readable than before.