php 生成唯一随机码
/** * 创建邀请码 * @param $length * @return array * @author Mr lj */ function createInvitationCode($num=1,$length=8) { $sign = ['_','#','$','&','*','-']; $mixedArr = array_merge(range('a','z'),range('A','Z'),range(0,9),$sign); $data = []; $i = 0; $str = ''; for($a=0;$a<$num;$a++) { while($i < $length) { $key = mt_rand(0,count($mixedArr)-1); $str .= $mixedArr[$key]; ++$i; } $res = M('SystemCode')->where(['code'=>$str])->find(); (($res == true) && --$a) || $data[] = $str; $str = ''; $i = 0; } return $data; }