1 /*
 2 随机打乱数组顺序，不是调用任何PHP内置随机函数
 3  */
 4     error_reporting(0);
 5     $arr = range(1,100);
 6     print_r(shuffleDiy($arr));
 7     function shuffleDiy($arr){
 8         $len = count($arr);
 9         if($len<=1){
10             return $arr;
11         }
12         for($i=0;$i<$len;$i++){
13             $temp = $arr[$i];
14             $rand = getRandNum($len);
15             $arr[$i] = $arr[$rand];
16             $arr[$rand] = $temp;
17         }
18         return $arr;
19     }
20     //生成随机数函数，传值数组长度，获取微秒的几个数字，作为随机数
21     function getRandNum($len){
22         $max = strlen($len);
23         $mic = current(explode(' ',microtime()));
24         $micc = next(explode('.',$mic));
25         $res = intval(substr(strrev($micc), 2,$max));
26         while($res>=$len){
27             $res = intval($res/2);
28         }
29         return $res;
30     }