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初学PHP,有一个有关问题

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Release: 2016-06-13 11:56:21
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初学PHP,有一个问题
看书上写了一些检验变量数据类型的函数,就试了试其中的一个

<br />$a = 5;<br />    echo is_int($a);<br />
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为什么打印的是1,a是一个整形变量,不应该返回true吗?
------解决方案--------------------
$a = 5;<br />echo is_int($a); //1<br />var_dump(is_int($a)); //bool(true)<br />
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true 转换为数值时就是 1
------解决方案--------------------
1为真 真就是true ,0为假 假就是false
------解决方案--------------------
你echo 就输出1 你var_dump就是true了!
------解决方案--------------------
<br />   $a = 5;<br />    echo var_dump(is_int($a));<br /><br />
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------解决方案--------------------
据说PHP源码中一个echo是经过10多层调用的,实在没echo过布尔值,估计是强制转成整数了
------解决方案--------------------
整型 bool true = 1 false = 0

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