js汉字转化为utf8

var mode="zhuan";
function encode(obj,btn){
    if(mode=="zhuan"){
        obj.value=obj.value.replace(/[^\u0000-\u00FF]/g,function($0){return escape($0).replace(/(%u)(\w{4})/gi,"&#x$2;")});
        btn.value="还原";
        mode="huan";
    }else{
        obj.value=unescape(obj.value.replace(/&#x/g,'%u').replace(/;/g,''));
        btn.value="转化";
        mode="zhuan";
    }