php生成随机数的三种方法_php技巧

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.gxlcms.com
foreach($return as $value)
 {
  echo $value." ";
 }
echo "
";
$arr=array_values($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 :
$chars='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
break;
} // www.gxlcms.com
mt_srand((double)microtime()*1000000*getmypid());
while(strlen($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 "
";
}