Return different array value depends on condition

var DEST_MAP = {
    '1': 'USA',
    '110000': 'Indiana',
    '230000': 'New York'
};
 
var DEST_MAP_UTF8 = {
    '1': 'USA',
    '110000': 'Indianapolis',
    '230000': 'New York City'
};
 
var doc = document, 
    EMPTY = '';
var charset = doc.charset || doc['characterSet'] || 'gb2312'; // set default charset to gb2312
var isUTF8 = charset.toLowerCase().indexOf('utf-8') != -1;
 
// bad way
var getDestNameByCode = (function() {
    if (isUTF8) {
        return function(destCode) {
            return DEST_MAP_UTF8[destCode] || EMPTY;
        }
    }
    else {
        return function(destCode) {
            return DEST_MAP[destCode] || EMPTY;
        }
    }
})();
 
// good
var getDestNameByCode = isUTF8 ?
    function(destCode) { return DEST_MAP_UTF8[destCode] || ""; } :
    function(destCode) { return DEST_MAP[destCode] || ""; };
 
// best
var MAP = isUTF8 ? DEST_MAP_UTF8 : DEST_MAP;
function getDestNameByCode(destCode) {
    return MAP[destCode] || EMPTY;
}