javascript - 多个嵌套 switch 语句的最佳替代方案？

Question

我有一个带有多个嵌套 switch case 的 JavaScript 函数，这完全是一团糟。这几个月功能一直在扩展，现在我想重组代码。在每种情况下，都应将不同的值推送到已存在的变量。

这是我的代码示例:

switch(var1){
    case 1:
        switch(var2){
            case 0:
                switch(var3){
                    case 'test':
                        switch(i){
                            case 0: endresult.push({id: i, content: '123'}); break;
                            case 2: endresult.push({id: i, content: '124'}); break;
                        }
                        break;
                    default:
                        endresult.push({id: i, content: '125'}); break;
                }
                break;
            case 1:
                endresult.push({id: i, content: '126'}); break;
        }
        break;
    case 2:
        switch(var2){
            case 0:
                switch(i){
                    case 0: endresult.push({id: i, content: '127'}); break;
                    case 2: endresult.push({id: i, content: '128'}); break;
                }
                break;
            case 1:
                switch(i){
                    case 0: endresult.push({id: i, content: '128'}); break;
                    case 2: endresult.push({id: i, content: '129'}); break;
                }
                break;
        }
        break;
}

重写它的最佳方法是什么？

Answer 1

拥有所有可能变体及其值的映射:

// Key is composite of `"" + var1 + "_" + var2 + "_" + i` and trimmed `_` from back

let tree = {
    '1_0_test_0': '123',
    '1_0_test_2': '124',
    '1_0_test': '125',
    '1_0_1': '126',
    ...
}

let key = ("" + var1 + var2 + i).replace(/_{2,}|_+$/, '');

if (typeof tree[key] !== 'undefined') {
    endresult.push({id: i, content: tree[key]});
}