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phprandomboolean

Get random boolean true/false in PHP


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

I can think of:

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

But does casting an integer to boolean bring any disadvantages?

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


Solution

  • 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;
    

    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)) { ... }
    

    Is a perfectly valid condition and will work as expected.

    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;
    

    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);