How to convert text to \x codes?

Question

I want to convert normal text to \\x codes for e.g \\x14\\x65\\x60

For example :

normal text = \"base64_decode\"
converted \\x codes for above text =         


        

Answer 1

For an alternative to dechex(ord()) you can also use bin2hex($char), sprintf('\x%02X') or unpack('H*', $char). Additionally instead of using preg_replace_callback, you can use array_map with str_split.

echo implode(array_map(function($char) {
    return '\x' . bin2hex($char);
}, (array) str_split($word)));

echo implode(array_map(function($char) {
    return '\x' . implode(unpack('H*', $char));
}, (array) str_split($word)));

echo implode(array_map(function($char) {
    return sprintf('\x%02X', ord($char));
}, (array) str_split($word)));

Example: https://3v4l.org/6Pc6X

bin2hex

echo implode(array_map(function($char) {
    return '\x' . bin2hex($char);
}, (array) str_split('base64_decode')));

Result

\x62\x61\x73\x65\x36\x34\x5f\x64\x65\x63\x6f\x64\x65

---

unpack

echo implode(array_map(function($char) {
    return '\x' . implode(unpack('H*', $char));
}, (array) str_split('base64_decode')));

Result

\x62\x61\x73\x65\x36\x34\x5f\x64\x65\x63\x6f\x64\x65

---

sprintf

echo implode(array_map(function($char) {
    return sprintf('\x%02X', ord($char));
}, (array) str_split('base64_decode')));

Result

\x62\x61\x73\x65\x36\x34\x5f\x64\x65\x63\x6f\x64\x65