php产生随机数的两种方法实例代码 输出随机IP
分享下php生成随机数的三种方法，生成1-10之间的不重复随机数，php生成不重复随机数的例子，需要的朋友参考下。
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.jb51.net
foreach($return as $value)
{
echo $value." ";
}
echo "<br/>";
$arr=array_values($return);// 获得数组的值
foreach($arr as $key)
echo $key." ";
?>
本人是asp程序员，这是首次写php程序，一点心得发上来共享
<?php
$ip2id= round(rand(600000, 2550000) / 10000); //第一种方法，直接生成
$ip3id= round(rand(600000, 2550000) / 10000);
$ip4id= round(rand(600000, 2550000) / 10000);
//下面是第二种方法，在以下数据中随机抽取
$arr_1 = array("218","218","66","66","218","218","60","60","202","204","66","66","66","59","61","60","222","221","66","59","60","60","66","218","218","62","63","64","66","66","122","211");
$randarr= mt_rand(0,count($arr_1)-1);
$ip1id = $arr_1[$randarr];
echo $ip1id;
echo ".";
echo $ip2id;
echo ".";
echo $ip3id;
echo ".";
echo $ip4id;
?>
例输出结果为 218.28.131.182
这个程序的特点是,生成的ip第一个字段时在指定范围内的，设定的几个是国内常见号段，也就是说生成的ip地址大部分是国内的
核心代码:
<?php
$arr_1 = array("http://66.249.89.99","http://66.249.89.104","http://74.125.71.105");
$randarr= mt_rand(0,count($arr_1)-1);
$gip= $arr_1[$randarr];
echo $gip."$randarr";
?>