PHP convert KB MB GB TB etc to Bytes

Question

I\'m asking how to convert KB MB GB TB & co. into bytes.
For example:

byteconvert(\"10KB\") // => 10240
byteconvert(\"10.5KB\") // =>          


        

Answer 1

Wanting something similar to this and not quite liking the other solutions posted here for various reasons, I decided to write my own function:

function ConvertUserStrToBytes($str)
{
    $str = trim($str);
    $num = (double)$str;
    if (strtoupper(substr($str, -1)) == "B")  $str = substr($str, 0, -1);
    switch (strtoupper(substr($str, -1)))
    {
        case "P":  $num *= 1024;
        case "T":  $num *= 1024;
        case "G":  $num *= 1024;
        case "M":  $num *= 1024;
        case "K":  $num *= 1024;
    }

    return $num;
}

It adapts a few of the ideas presented here by Al Jey (whitespace handling) and John V (switch-case) but without the regex, doesn't call pow(), lets switch-case do its thing when there aren't breaks, and can handle some weird user inputs (e.g. " 123 wonderful KB " results in 125952). I'm sure there is a more optimal solution that involves fewer instructions but the code would be less clean/readable.