Unicode ⇔ UTF-8

Unicode ⇔ UTF-8
/**********************************************************************
*
* Unicode ⇔ UTF-8
*
* Copyright (c) 2005 AOK
*
**********************************************************************/
function _to_utf8(s) {
var c, d = "";
for (var i = 0; i < s.length; i++) {
c = s.charCodeAt(i);
if (c <= 0x7f) {
d += s.charAt(i);
} else if (c >= 0x80 && c <= 0x7ff) {
d += String.fromCharCode(((c >> 6) & 0x1f) 0xc0);
d += String.fromCharCode((c & 0x3f) 0x80);
} else {
d += String.fromCharCode((c >> 12) 0xe0);
d += String.fromCharCode(((c >> 6) & 0x3f) 0x80);
d += String.fromCharCode((c & 0x3f) 0x80);
}
}
return d;
}
function _from_utf8(s) {
var c, d = "", flag = 0, tmp;
for (var i = 0; i < s.length; i++) {
c = s.charCodeAt(i);
if (flag == 0) {
if ((c & 0xe0) == 0xe0) {
flag = 2;
tmp = (c & 0x0f) << 12;
} else if ((c & 0xc0) == 0xc0) {
flag = 1;
tmp = (c & 0x1f) << 6;
} else if ((c & 0x80) == 0) {
d += s.charAt(i);
} else {
flag = 0;
}
} else if (flag == 1) {
flag = 0;
d += String.fromCharCode(tmp (c & 0x3f));
} else if (flag == 2) {
flag = 3;
tmp = (c & 0x3f) << 6;
} else if (flag == 3) {
flag = 0;
d += String.fromCharCode(tmp (c & 0x3f));
} else {
flag = 0;
}
}
return d;
}