can I get the unicode value of a character or vise versa with php?

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?

Solution

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()