实现文件单位的快速转换,这是我的第一个函数

unitConvert.php

<?php
/**
 * Created by PhpStorm
 * User: Xinyu
 * Date: 16/8/25
 * Time: 下午10:09
 */
function unitConvert($scale){
    if($scale >= (1<<30)){
        $scale /= (1<<30);
        $scale = round($scale,2);
        echo $scale,'GB';
    }else if($scale >= (1<<20)){
        $scale /= (1<<20);
        $scale = round($scale,2);
        echo $scale,'MB';
    }else if($scale >= (1<<10)){
        $scale /= (1<<10);
        $scale = round($scale,2);
        echo $scale,'KB';
    }else{
        echo $scale,'B';
    }
}

?>

function byteConvert($size) {
    switch ($size) {
        case $size >= 1 << 50:
            $unit = 1 << 50;
            $unit_name = 'PB';
            break;
        case $size >= 1 << 40:
            $unit = 1 << 40;
            $unit_name = 'TB';
            break;
        case $size >= 1 << 30:
            $unit = 1 << 30;
            $unit_name = 'GB';
            break;
        case $size >= 1 << 20:
            $unit = 1 << 20;
            $unit_name = 'MB';
            break;
        case $size >= 1 << 10:
            $unit = 1 << 10;
            $unit_name = 'KB';
            break;
        default:
            $unit = $size;
            $unit_name = 'B';
    }

    $size /= $unit;

    return round($size, 2) . $unit_name;
}