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"; 
    ?>