什么是+ =用于？

我认为这是一个愚蠢的问题,但我无法在PHP上找到它.为什么在以下代码中带有=的+:

function calculateRanking()
{
    $created = $this->getCreated();

    $diff = $this->getTimeDifference($created, date('F d, Y h:i:s A'));

    $time = $diff['days'] * 24;
    $time += $diff['hours'];
    $time += ($diff['minutes'] / 60);
    $time += (($diff['seconds'] / 60)/60);

    $base = $time + 2;        

    $this->ranking = ($this->points - 1) / pow($base, 1.5);

    $this->save();
}

这是多少时间有所有这些值,或者更确切地说它是将所有值添加到$ time？

谢谢

它将所有这些值添加到时间.

something += somethingelse

是一个快捷方式

something = something + somethingelse

-亚当

$time += $diff['hours'];

$time = $time + $diff['hours'];