PHP Unpack a single byte from a binary string

Question

I have a raw string of bytes $b coming from

$b=sha1($k,true);

I need to know the value of $b[$ix]. The only way I've found is

$arr=unpack('Cw',$b[$ix]);
$value=$arr["w"];

But for such elemental operation it seems too much overload.

Is there a more straight way to access the bytes in a raw string?

just treat it as an array of bytes: $foo = 'abc123'; echo $foo[2] outputs c. — Marc B
– Marc B, Commented Jul 22, 2016 at 20:01

LF-DevJourney · Accepted Answer · 2016-07-23 07:43:50Z

2

Ascii value:

$b=sha1($k,true);
echo ord($b[$ix]);

answered Jul 23, 2016 at 7:43

LF-DevJourney

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2 Comments

This also works, $b=sha1($k); echo $b[2 * $ix] * 16 + $b[2 * $ix + 1];

$arr=unpack('C',$b[$ix]); $value=$arr[1];