can I get the unicode value of a character or vise

问题:

Is it possible to input a character and get the unicode value back? for example, i can put &#12103 in html to output "⽇", is it possible to give that character as an argument to a function and get the number as an output without building a unicode table?

$val = someFunction("⽇");//returns 12103

or the reverse?

$val2 = someOtherFunction(12103);//returns "⽇"

I would like to be able to output the actual characters to the page not the codes, and I would also like to be able to get the code from the character if possible. The closest I got to what I want is php.net/manual/en/function.mb-decode-numericentity.php but I cant get it working, is this the code I need or am I on the wrong track?

回答1:

function _uniord($c) {
    if (ord($c{0}) >=0 && ord($c{0}) <= 127)
        return ord($c{0});
    if (ord($c{0}) >= 192 && ord($c{0}) <= 223)
        return (ord($c{0})-192)*64 + (ord($c{1})-128);
    if (ord($c{0}) >= 224 && ord($c{0}) <= 239)
        return (ord($c{0})-224)*4096 + (ord($c{1})-128)*64 + (ord($c{2})-128);
    if (ord($c{0}) >= 240 && ord($c{0}) <= 247)
        return (ord($c{0})-240)*262144 + (ord($c{1})-128)*4096 + (ord($c{2})-128)*64 + (ord($c{3})-128);
    if (ord($c{0}) >= 248 && ord($c{0}) <= 251)
        return (ord($c{0})-248)*16777216 + (ord($c{1})-128)*262144 + (ord($c{2})-128)*4096 + (ord($c{3})-128)*64 + (ord($c{4})-128);
    if (ord($c{0}) >= 252 && ord($c{0}) <= 253)
        return (ord($c{0})-252)*1073741824 + (ord($c{1})-128)*16777216 + (ord($c{2})-128)*262144 + (ord($c{3})-128)*4096 + (ord($c{4})-128)*64 + (ord($c{5})-128);
    if (ord($c{0}) >= 254 && ord($c{0}) <= 255)    //  error
        return FALSE;
    return 0;
}   //  function _uniord()

and

function _unichr($o) {
    if (function_exists('mb_convert_encoding')) {
        return mb_convert_encoding('&#'.intval($o).';', 'UTF-8', 'HTML-ENTITIES');
    } else {
        return chr(intval($o));
    }
}   // function _unichr()

回答2:

Here's a more compact implementation of unichr/uniord based on pack:

// code point to UTF-8 string
function unichr($i) {
    return iconv('UCS-4LE', 'UTF-8', pack('V', $i));
}

// UTF-8 string to code point
function uniord($s) {
    return unpack('V', iconv('UTF-8', 'UCS-4LE', $s))[1];
}

回答3:

This also works, (for someone who understands bitshifting this might be more readable than Mark Bakers answer):

public function ordinal($str){
    $charString = mb_substr($str, 0, 1, 'utf-8');
    $size = strlen($charString);        
    $ordinal = ord($charString[0]) & (0xFF >> $size);
    //Merge other characters into the value
    for($i = 1; $i < $size; $i++){
        $ordinal = $ordinal << 6 | (ord($charString[$i]) & 127);
    }
    return $ordinal;
}

回答4:

You can use the following functions

For encoding

string utf8_encode ( string $data )

http://php.net/manual/en/function.utf8-encode.php

For decoding

string utf8_decode ( string $data )

http://php.net/manual/en/function.utf8-decode.php

Also check

http://php.net/manual/en/function.htmlspecialchars.php

<?php


echo htmlspecialchars_decode("&#12103");//will print ⽇

?>

回答5:

If you're using PHP7.2 (or later), you don't need to define a new function; there exist two functions for your purposes from Multibyte String extension/library!

To get code point of a character (i.e. Unicode value), use mb_chr(); and to get a specific character from that value, use mb_ord().

E.g.:

mb_chr(12103, "utf8"); // ⽇
mb_ord("⽇", "utf8"); // 12103