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关于microtime()函数的有关问题

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Jun 13, 2016 pm 12:21 PM

nbsptrue

关于microtime()函数的问题
我分别在程序的开头和结尾用microtime()函数取得当前时间，然后相减得到程序运行时间，在5.2版本的php上没问题，但是在5.3、5.4和5.5三个版本的php相减结果不是0就是0.0156，跟5.2.6版本的完全不同，这是怎么回事啊？
------解决思路----------------------

$startTime=microtime(true);<br />for($i=0;$i<1000000; $i++) {<br />  $a = 1;<br />}<br />printf("%.16f",microtime(true)-$startTime);

0.0468750000000000

这就是版本的威力了
你可以改变循环的终值，使得各种版本下都有输出
然后你就会发现：每提高一个种版本号，时间就会缩小至少一个数量级
------解决思路----------------------
不同版本的运行时间不一样很正常。
高版本的比低版本的优化过，当然时间花费少很多。

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