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PHP7 新特性之?:和??的区别

本文是关于介绍PHP中 ?: 和 ?? 这两个添加的新特性,并用代码来解释说明,感兴趣的朋友可以了解一下。

?:和??是PHP添加的新特性,我们可以通过下面的代码来理解

$z = $x ?? $y;//等价于下面$z = isset($x) ? $x : $y;$z = $x ?: $y;//等价于下面$z = $x ? $x : $y;

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文章来源:智云一二三科技

文章标题:PHP7 新特性之?:和??的区别

文章地址:https://www.zhihuclub.com/5546.shtml

关于作者: 智云科技

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