UTF8编码解码函数_c语言utf8解码

<script>
function encode_utf8(rawtext) {
    rawtext = rawtext.replace(//r/n/g,"/n");
    var utftext = "";
    for(var n=0; n<rawtext.length; n++)
        {
        //
        var c=rawtext.charCodeAt(n);
        // 0-127 => 1byte
        if (c<128)
            utftext += String.fromCharCode(c);
        // 127 - 2047 => 2byte
        else if((c>127) && (c<2048)) {
            utftext += String.fromCharCode((c>>6)|192);
            utftext += String.fromCharCode((c&63)|128);}
        // 2048 - 66536 => 3byte
        else {
            utftext += String.fromCharCode((c>>12)|224);
            utftext += String.fromCharCode(((c>>6)&63)|128);
            utftext += String.fromCharCode((c&63)|128);}
        }
    return utftext;
}

function decode_utf8(utftext) {
    var plaintext = ""; var i=0; var c=c1=c2=0;
    while(i<utftext.length)
        {
        c = utftext.charCodeAt(i);
        if (c<128) {
            plaintext += String.fromCharCode(c);
            i++;}
        else if((c>191) && (c<224)) {
            c2 = utftext.charCodeAt(i+1);
            plaintext += String.fromCharCode(((c&31)<<6) | (c2&63));
            i+=2;}
        else {
            c2 = utftext.charCodeAt(i+1); c3 = utftext.charCodeAt(i+2);
            plaintext += String.fromCharCode(((c&15)<<12) | ((c2&63)<<6) | (c3&63));
            i+=3;}
        }
    return plaintext;
}
</script>