在 PHP 中获取随机布尔值真/假

2022-01-19 00:00:00 random boolean php

在 PHP 中获得随机布尔真/假的最优雅的方法是什么?

What would be the most elegant way to get a random boolean true/false in PHP?

我能想到:

$value = (bool)rand(0,1);

但是将整数转换为布尔值有什么缺点吗?

But does casting an integer to boolean bring any disadvantages?

或者这是一种官方"的方式来做到这一点?

Or is this an "official" way to do this?

推荐答案

如果您不希望进行布尔类型转换(并不是说这有什么问题)，您可以像这样轻松地将其设置为布尔值:

If you don't wish to have a boolean cast (not that there's anything wrong with that) you can easily make it a boolean like this:

$value = rand(0,1) == 1;

基本上，如果随机值为1，则产生true，否则false.当然，0 或 1 的值已经充当布尔值；所以这个:

Basically, if the random value is 1, yield true, otherwise false. Of course, a value of 0 or 1 already acts as a boolean value; so this:

if (rand(0, 1)) { ... }

是一个完全有效的条件，将按预期工作.

Is a perfectly valid condition and will work as expected.

或者，您可以使用 mt_rand() 生成随机数(这是对 rand()).您甚至可以使用以下代码达到 openssl_random_pseudo_bytes():

Alternatively, you can use mt_rand() for the random number generation (it's an improvement over rand()). You could even go as far as openssl_random_pseudo_bytes() with this code:

$value = ord(openssl_random_pseudo_bytes(1)) >= 0x80;

更新
在 PHP 7.0 中，您将能够使用 random_int()，它会生成加密安全的伪随机数整数:

Update

In PHP 7.0 you will be able to use random_int(), which generates cryptographically secure pseudo-random integers:

$value = (bool)random_int(0, 1);

相关文章