Convert unicode characters above 127 to decimal [duplicate]
Question
Possible Duplicate:
How to convert text to unicode code point like \u0054\u0068\u0069\u0073 using php?
I'm trying to convert all characters that can't fit into a 7-bit ANSI character into an escaped form, \uN
, where N
is its decimal value. Here's what I've come up with:
private static function escape($str) {
return preg_replace_callback('~[\\x{007F}-\\x{FFFF}]~u',function($m){return '\\u'.ord($m[0]);},$str);
}
I've tried it with characters like Gamma,
echo self::escape('Γ');
But I get \u206
back out instead of \u915
. I can't figure out where I'm going wrong... ideas?
Actually, it appears that either the ord()
function doesn't give me the value or I want, or maybe the encoding on my .php file is wrong?
Solution
I had to refresh my memory on exactly how UTF-8 works, but here is a utf8_ord()
function, and a complementing utf8_chr()
. The chr()
is lifted pretty much verbatim from my answer here.
function utf8_ord ($chr)
{
$bytes = array_values(unpack('C*', $chr));
switch (count($bytes)) {
case 1:
return $bytes[0] < 0x80
? $bytes[0]
: false;
case 2:
return ($bytes[0] & 0xE0) === 0xC0 && ($bytes[1] & 0xC0) === 0x80
? (($bytes[0] & 0x1F) << 6) | ($bytes[1] & 0x3F)
: false;
case 3:
return ($bytes[0] & 0xF0) === 0xE0 && ($bytes[1] & 0xC0) === 0x80 && ($bytes[2] & 0xC0) === 0x80
? (($bytes[0] & 0x0F) << 12) | (($bytes[1] & 0x3F) << 6) | ($bytes[2] & 0x3F)
: false;
case 4:
return ($bytes[0] & 0xF8) === 0xF0 && ($bytes[1] & 0xC0) === 0x80 && ($bytes[2] & 0xC0) === 0x80 && ($bytes[3] & 0xC0) === 0x80
? (($bytes[0] & 0x07) << 18) | (($bytes[1] & 0x3F) << 12) | (($bytes[2] & 0x3F) << 6) | ($bytes[3] & 0x3F)
: false;
}
return false;
}
function utf8_chr ($ord)
{
switch (true) {
case $ord < 0x80:
return pack('C*', $ord & 0x7F);
case $ord < 0x0800:
return pack('C*', (($ord & 0x07C0) >> 6) | 0xC0, ($ord & 0x3F) | 0x80);
case $ord < 0x010000:
return pack('C*', (($ord & 0xF000) >> 12) | 0xE0, (($ord & 0x0FC0) >> 6) | 0x80, ($ord & 0x3F) | 0x80);
case $ord < 0x110000:
return pack('C*', (($ord & 0x1C0000) >> 18) | 0xF0, (($ord & 0x03F000) >> 12) | 0x80, (($ord & 0x0FC0) >> 6) | 0x80, ($ord & 0x3F) | 0x80);
}
return false;
}