Random Functions in PHP

Random values are very important in many situations. Random values can be used to generate strings for passwords, quotes, and CAPTCHAs. They can also be used for grabbing random numbers for games and other purposes.

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1. Random Integer

function get_random_number($min = 0, $max = 100) {
return rand($min,$max);
}

2. Random String - From Word List (Array)

function get_random_string_from_list($list_of_words) {
return $list_of_words[rand(0, sizeof($list_of_words)-1)];
}

3. Random String

function get_random_string($length=6,$characters = "ABCDEFGHIJKLMNOPRQSTUVWXYZ") {
$num_characters = strlen($characters) - 1;
while (strlen($return) < $length) {
$return.= $characters[mt_rand(0, $num_characters)];
}
return $return;
}

4. Random Float

function random_float ($min, $max) {
return ($min + lcg_value() * (abs($max-$min)));
}

5. Random Hex Color

function get_random_hex_color($values = 'abcdef0123456789',$length=6) {
$num_characters = strlen($characters) - 1;
while (strlen($code) < $length) {
$return.= $characters[mt_rand(0, $num_characters)];
}
return '#'.$return;
}

6. Random File From Directory

function get_random_file($dir) {
while (false !== ($file = readdir($dir))) {
$files[] = $file;
}
return $files[rand(0, sizeof($files)-1)];
}