php和js实现转换文件大小为人性化可读的方式

<?php
function my_formatSize($size){
$size  = doubleval($size);
$rank =0;
$rankchar ='Bytes';
while($size>1024){
    $size = $size/1024;
    $rank++;
}
if($rank==1){
    $rankchar="KB";
}
else if($rank==2){
    $rankchar="MB";
}
else if($rank==3){
    $rankchar="GB";
}
$size = number_format($size, 2, '.', '');
return  "".$size." ".$rankchar;
}

<?php
function my_formatSize($size){
    var size  = parseFloat($size);
    var rank =0;
    var rankchar ='Bytes';
    while(size>1024){
size = size/1024;
rank++;
    }
    if(rank==1){
rankchar="KB";
    }
    else if(rank==2){
rankchar="MB";
    }
    else if(rank==3){
rankchar="GB";
    }   
    return size.toFixed(2)+ " "+ rankchar;
}
?>