简化长 Switch 语句

我需要温习我的 javascript，因为它是我最弱的语言，所以我想“嘿，让我们制作一个简单的‘翻译’程序来测试我的技能”。好吧，到目前为止，我能够以一种方式翻译它（我还没有尝试过翻译人们输入的内容），但无论如何，它的方式是通过开关内的一系列许多情况来实现的。我想知道是否有办法简化代码，而不是拥有一百万个开关案例。谢谢这是我的代码。

function main() {
            var get = prompt("Enter what you would like to encode!","At the current time decoding is still a WIP").toLowerCase();
            var ina = [...get];
            for(i = 0; i < ina.length; i++) {
                switch(ina[i]) {
                case "a":
                    ina[i] = "z";
                    break;
                case "b":
                    ina[i] = "y";
                    break;
                case "c":
                    ina[i] = "x";
                    break;
                case "d":
                    ina[i] = "w";
                    break;
                case "e":
                    ina[i] = "v";
                    break;
                case "f":
                    ina[i] = "u";
                    break;
                case "g":
                    ina[i] = "t";
                    break;
                case "h":
                    ina[i] = "s";
                    break;
                case "i":
                    ina[i] = "r";
                    break;
                case "j":
                    ina[i] = "q";
                    break;
                case "k":
                    ina[i] = "p";
                    break;
                case "l":
                    ina[i] = "o";
                    break;
                case "m":
                    ina[i] = "n";
                    break;
                case "n":
                    ina[i] = "m";
                    break;
                case "o":
                    ina[i] = "l";
                    break;
                case "p":
                    ina[i] = "k";
                    break;
                case "q":
                    ina[i] = "j";
                    break;
                case "r":
                    ina[i] = "i";
                    break;
                case "s":
                    ina[i] = "h";
                    break;
                case "t":
                    ina[i] = "g";
                    break;
                case "u":
                    ina[i] = "f";
                    break;
                case "v":
                    ina[i] = "e";
                    break;
                case "w":
                    ina[i] = "d";
                    break;
                case "x":
                    ina[i] = "c";
                    break;
                case "y":
                    ina[i] = "b";
                    break;
                case "z":
                    ina[i] = "a";
                    break;
                default:
                    ina[i] = ina[i]
                    };
                };
                var outa = ina.join("");
                document.getElementById("output").innerHTML = outa;

            };      

您可以使用具有以下属性的对象

{
    a: 'z',
    b: 'y',
    c: 'x',
    // ...
    z: 'a'
}

使用默认值ina[i].

ina[i] = object[ina[i]] || ina[i];