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HomeBackend DevelopmentPHP TutorialPHP中0和空的区别详解

作为一个合格的php程序员,一些基础知识是必须要知道的,例如0和空的区别,关于这个区别。

下面就通过几个实例进行简单的分析,其中的道理,只可意会,不可言传,读者可以自己去慢慢体会了。

<span style="font-size: 14px;"><?php</span><br />$test=0;<br /><br />if($test==''){<br />echo '<br />在php中,0即为空'; //被输出<br />}<br /><br />if($test===''){<br />echo '<br />在php中,0即为空'; //不被输出<br />}<br /><br />if($test==NULL){<br />echo '<br />在php中,0即为空'; //被输出<br />}<br /><br />if($test===NULL){<br />echo '<br />在php中,0即为空'; //不被输出<br />}<br /><br />if($test==false){<br />echo '<br />在php中,0即为空'; //被输出<br />}<br /><br />if($test===false){<br />echo '<br />在php中,0即为空'; //不被输出<br />}<br /><br />?>


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