php取数组随机数

$a=Array ( [0] => Array ( [0] => 8 [face_amount] => 8 ) [1] => Array ( [0] => 30 [face_amount] => 30 ) [2] => Array ( [0] => 50 [face_amount] => 50 ) [3] => Array ( [0] => 50 [face_amount] => 50 ) );//从数据库里取出的数据

//二维数组取一个值

$b=(array_rand($a,1)); 

echo $a[$b]['face_amount'];

//二维数组取多个值

$c=(array_rand($a,2)); 

echo $a[$c[0]]['face_amount'];

echo $a[$c[1]]['face_amount'];

//定义一个二维数组

$a=array(

  array("Volvo",22,18),

  array("BMW",25,13),

  array("Saab",5,2),

  array("Land Rover",17,15)

  );

//获取一个

$b=(array_rand($a,1));

var_dump($a[$b][0]);

//获取多个

$b=(array_rand($a,2));

var_dump($a[$b[0]][0]);

var_dump($a[$b[1]][1]);