javascript - 如何知道一个数达到限制整数

Question

Assume we are dealing with an environment which could only store integers within the 32-bit signed integer range: [−2³¹, 2³¹ − 1]. For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.

我遇到的问题是如何知道一个数字大于整数范围。 (抱歉我的英语不好)

Answer 1

您可以从 Signed 32-bit integers 获取值并检查范围。

function getValue(v) {
    return v < -2147483648 || v > 2147483647
        ? 0
        : v;
}

console.log(getValue(1));
console.log(getValue(1e20));