PHP Manual: Decode HTML numeric string reference to character

Description

string mb_decode_numericentity(string $string, array $map, stringnull $encoding = null)

Convert numeric string reference of string string in a specified block to character.

Parameters

string: The string being decoded.
map: map is an array that specifies the code area to convert.
encoding: The encoding parameter is the character encoding. If it is omitted or null, the internal character encoding value will be used.
is_hex: This parameter is not used.

Return Values

The converted string.

Errors/Exceptions

Throws a ValueError if map is not a list of ints.

Changelog

Version	Description
8.4.0	mb_decode_numericentity now throws a ValueError if `map` is not a list of ints.
8.0.0	`encoding` is nullable now.

Examples

Example #1 map example

<?php
$convmap = array (
   int start_code1, int end_code1, int offset1, int mask1,
   int start_code2, int end_code2, int offset2, int mask2,
   ........
   int start_codeN, int end_codeN, int offsetN, int maskN );
// Specify Unicode value for start_codeN and end_codeN
// Add offsetN to value and take bit-wise 'AND' with maskN, 
// then convert value to numeric string reference.
?>

Example #2 map example escapes JavaScript string

<?php
function escape_javascript_string($str) {
  $map = [
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,0,0, // 49
          0,0,0,0,0,0,0,0,1,1,
          1,1,1,1,1,0,0,0,0,0,
          0,0,0,0,0,0,0,0,0,0,
          0,0,0,0,0,0,0,0,0,0,
          0,1,1,1,1,1,1,0,0,0, // 99
          0,0,0,0,0,0,0,0,0,0,
          0,0,0,0,0,0,0,0,0,0,
          0,0,0,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1, // 149
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1, // 199
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1,
          1,1,1,1,1,1,1,1,1,1, // 249
          1,1,1,1,1,1,1, // 255
          ];
  // Char encoding is UTF-8
  $mblen = mb_strlen($str, 'UTF-8');
  $utf32 = bin2hex(mb_convert_encoding($str, 'UTF-32', 'UTF-8'));
  for ($i=0, $encoded=''; $i < $mblen; $i++) {
      $u = substr($utf32, $i*8, 8);
      $v = base_convert($u, 16, 10);
      if ($v < 256 && $map[$v]) {
        $encoded .= '\\x'.substr($u, 6,2);
      } else if ($v == 2028) {
        $encoded .= '\\u2028';
      } else if ($v == 2029) {
        $encoded .= '\\u2029';
      } else {
        $encoded .= mb_convert_encoding(hex2bin($u), 'UTF-8', 'UTF-32');
      }
   }
   return $encoded;
}
 
// Test data
$convmap = [ 0x0, 0xffff, 0, 0xffff ];
$msg = '';
for ($i=0; $i < 1000; $i++) {
  // chr() cannot generate correct UTF-8 data larger value than 128, use mb_decode_numericentity().
  $msg .= mb_decode_numericentity('&#'.$i.';', $convmap, 'UTF-8');
}
 
// var_dump($msg);
var_dump(escape_javascript_string($msg));

mb_decode_numericentity