PHP array_rand () function
Examples
It returns an array containing the random key names:
<?php
$a=array("red","green","blue","yellow","brown");
$random_keys=array_rand($a,3);
echo $a[$random_keys[0]]."<br>";
echo $a[$random_keys[1]]."<br>";
echo $a[$random_keys[2]];
?>
$a=array("red","green","blue","yellow","brown");
$random_keys=array_rand($a,3);
echo $a[$random_keys[0]]."<br>";
echo $a[$random_keys[1]]."<br>";
echo $a[$random_keys[2]];
?>
Running instance »
Definition and Usage
array_rand () function returns an array of random keys, or if the specified function returns the name of more than one key, it returns an array containing the random key name.
grammar
array_rand( array,number )
| 参数 | 描述 |
|---|---|
| array | 必需。规定数组。 |
| number | 可选。规定返回多少个随机的元素。 |
technical details
| return value: | Returns a random array of keys, or if the specified function returns the name of more than one key, it returns an array containing the random key name. |
|---|---|
| PHP version: | 4+ |
| Update log: | Since PHP 5.2.10 onwards, the results of an array of keys is no longer ay of keys is no longer shuffled. As of PHP 4.2.0, the random number generator is automatically seeded. |
More examples
Example 1
Returns a random array of keys:
<?php
$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r(array_rand($a,1));
?>
$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r(array_rand($a,1));
?>
Running instance »
Example 2
It returns an array containing a random string of key names:
<?php
$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r(array_rand($a,2));
?>
$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow");
print_r(array_rand($a,2));
?>
Running instance »
Complete PHP Array Reference