How to convert a UTF-8 string to HEX codepoint in PHP?

Question

I get the HEX codepoint from a UTF-8 string via json_encode as

substr(json_encode($str), 1, -1);

However, json_encode does not convert the characters at the ASCII range. For example,

For

sÆs

I get

s\u00C6s

but I want to get

\u0073\u00C6\u0073

https://stackoverflow.com/a/35213288/476 – deceze Jan 29 '20 at 15:15 — deceze, Jan 29 '20 at 15:15

score 1 · Accepted Answer · answered Jan 29 '20 at 15:06

I take json_encode for multibyte characters and assemble it for the ASCII characters.

function utf8toUnicode($str){
  $unicode = "";
  $len = mb_strlen($str);
  for($i=0;$i<$len;$i++){
    $utf8char = mb_substr($str,$i,1);
    $unicode .= strlen($utf8char)>1
      ?trim(json_encode($utf8char),'"')
      :('\\u00'.bin2hex($utf8char))
    ;
  }
  return $unicode;
} 

$str = 'sÆs'; 

echo utf8toUnicode($str);  // \u0073\u00c6\u0073

How to convert a UTF-8 string to HEX codepoint in PHP?

1 Answers1