javascript - map 究竟如何排序键？

Question

我在 javascript 中对 json 进行数字签名，以通过 C++ 进行验证。我正在使用 json spirit解析将 map 用于 json Object 的 json，因此 Object 需要按照与 c++ map 。

An Object can easily be sorted by javascript

function sortObject(o) {
    var sorted = {},
    key, a = [];

    for (key in o) {
        if (o.hasOwnProperty(key)) {
            a.push(key);
        }
    }

    a.sort();

    for (key = 0; key < a.length; key++) {
        sorted[a[key]] = o[a[key]];
    }
    return sorted;
}

但是，我不确定 exact sorting method that c++ uses .

上面的代码是否足以让 javascript 以与 map 键排序相同的方式对 Object 键进行排序？如果没有，怎么办？

Answer 1

你基本上是在问 this问题。正如最佳答案所述:

Yes, that's [the iteration order is] guaranteed. Moreover, *begin() gives you the smallest and *rbegin() the largest element, as determined by the comparison operator, and two key values a and b for which the expression !compare(a,b) && !compare(b,a) is true are considered equal. The default comparison function is std::less.