var select = document.querySelector('select');
    var button =  document.querySelector('button');
    var alf = "qwertyuioplkjhgfdsazxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM";
    button.addEventListener('click', function(){
        var $text = $("#before").val();
        console.log($text);
        console.log(alf.length);
        if (select.value=="crypt")
        {
            for (var i=0;i<$text.length;i++){
                var check = 0;
                var num;
                console.log($text[i]);
                for (var j=0;j<alf.length;j++){
                    console.log(alf[j]);
                    if (String($text[i])===String(alf[j]))
                    {
                        check++;
                        console.log(check);
                        num=j;
                        break;
                    }
                }
                console.log(check);
                if (check>0)
                {
                    String($text[i])==String(alf[(num+2)%26]);
                }
            }
            console.log($text);
        }
        else
        {
            for (var i=0;i<$text.length;i++){
                var check = 0;
                for (var j=0; j<alf.length;j++){
                    if ($text[i]===alf[j])
                    {
                        check++;
                    }
                }
                if (check>0)
                {
                    $text[i]==alf[(j+2)%26];
                }
            }
            console.log($text);
        }
    });