帮忙看个源码
<html><head></head><body><?php$filename = 'english.dat'; //数据文件名$refresh = 1; //更新周期（以秒为单位，可根据需要自行调整）$data = file($filename); //将数据文件装入一个数组$num_lines = count($data); //数据文件行数，也就是记录条数 mt_srand(floor(time() / $refresh));$id = mt_rand(0, $num_lines - 1); //随机选择一条记录号$content = chop($data[$id]); //根据记录号选择相应的数据，并截去最后的换行符echo $content; //用javascript形式输出数据?></body></html>
这个是我从网上找到定时更新页面的源码，我想问下这个实现定时功能就是没有注释那段是什么意思，我不是很理解。
回复讨论(解决方案)
没有看到有定时更新的功能，是php随机取一个数组元素输出。或者你还有其他代码？
mt_srand 播种随机数发生器种子
没有看到有定时更新的功能，是php随机取一个数组元素输出。或者你还有其他代码？
refresh设置数值大点就不会变化，貌似是这个refresh在控制时间。
mt_srand 播种随机数发生器种子
这个和定时更新什么关系？不懂。
你问的是 没有注释那段是什么意思
至于 和定时更新什么关系 那你自己想吧
是你自己说是 定时更新页面的源码 的
因为当随机种子一样是，用到mt_rand()出来次序是一定的，也就是说随机种子一样，假设第一次执行第一次调用mt_rand等于5，每次执行第一次调用mt_rand都是等于5
而因为time()是时间戳，也就是秒数，如果你设置refresh为30, 那么假设某次time()是300,那么从这里开始的30秒一定是300，301，302，303，……329
用 300，301，302，303，……329 分别 除以 30，商的整数部分是一致的，所以
$id = mt_rand(0, $num_lines - 1);
这个id在这个30秒都是不发生变化的，那么下个30秒内肯定就会发生变化，这样就起到了30一个周期定时刷新
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