- implode: documentation ( source)
- strtoupper: documentation ( source)
<?php
function _hex2bin($hex)
{
$hex = strtoupper($hex);
$hexLen = strlen($hex);
$bin = [];
for ($i = 0; $i < $hexLen; $i++) {
$char = $hex[$i];
if ($char == '0') $bin[] = "0000";
else if ($char == '1') $bin[] = "0001";
else if ($char == '2') $bin[] = "0010";
else if ($char == '3') $bin[] = "0011";
else if ($char == '4') $bin[] = "0100";
else if ($char == '5') $bin[] = "0101";
else if ($char == '6') $bin[] = "0110";
else if ($char == '7') $bin[] = "0111";
else if ($char == '8') $bin[] = "1000";
else if ($char == '9') $bin[] = "1001";
else if ($char == 'A') $bin[] = "1010";
else if ($char == 'B') $bin[] = "1011";
else if ($char == 'C') $bin[] = "1100";
else if ($char == 'D') $bin[] = "1101";
else if ($char == 'E') $bin[] = "1110";
else if ($char == 'F') $bin[] = "1111";
else $bin[] = "0000";
}
return implode("", $bin);
}
echo _hex2bin("152F302436152F302435152F302434152F302433152F302433");