php生成随机数的三种方法


  本文标签:随机数

如何用php生成1-10之间的不重复随机数?

例1,使用shuffle函数生成随机数 。

<?php
$arr=range(1,10);
shuffle($arr);
foreach($arr as $values)
{
  echo $values." ";
}
?>

例2,使用array_unique函数生成随机数 。

<?php
$arr=array();
while(count($arr)<10)
{
  $arr[]=rand(1,10);
  $arr=array_unique($arr);
}
echo implode(" ",$arr);
?>

例3,使用array_flip函数生成随机数,可以去掉重复值 。

<?php
$arr=array();
$count1=0;
$count = 0;
$return = array();
while ($count < 10) 
 {
  $return[] = mt_rand(1, 10);
  $return = array_flip(array_flip($return));
  $count = count($return);
 } //www.jbxue.com
foreach($return as $value)
 {
  echo $value." ";
 }
echo "<br/>";
$arr=array_values($return);// 获得数组的值 
foreach($arr as $key)
echo $key." ";
?>

php随机数生成函数示例

<?php
function randpw($len=8,$format=ALL){
$is_abc = $is_numer = 0;
$password = $tmp =;  
switch($format){
case ALL:
$chars=ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789;
break;
case CHAR:
$chars=ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz;
break;
case NUMBER:
$chars=0123456789;
break;
default :
$chars=ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789;
break;
} // www.jbxue.com
mt_srand((double)microtime()*1000000*getmypid());
while(strlen($password)<$len){
$tmp =substr($chars,(mt_rand()%strlen($chars)),1);
if(($is_numer <> 1 && is_numeric($tmp) && $tmp > 0 )|| $format == CHAR){
$is_numer = 1;
}
if(($is_abc <> 1 && preg_match(/[a-zA-Z]/,$tmp)) || $format == NUMBER){
$is_abc = 1;
}
$password.= $tmp;
}
if($is_numer <> 1 || $is_abc <> 1 || empty($password) ){
$password = randpw($len,$format);
}
return $password;
}
for($i = 0 ; $i < 10; $i++){
echo randpw(8,NUMBER);
echo "<br>";
}