多维数组有更简单的方法来判断和赋值吗？

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if(!isset($cache_post_metas['post-1')) $cache_post_metas['post-1'] = array();
if(!isset($cache_post_metas['post-1']['thumbnail'])) $cache_post_metas['post-1']['thumbnail'] = array();
if(!isset($cache_post_metas['post-1']['thumbnail']['thumb'])) $cache_post_metas['post-1']['thumbnail']['thumb'] = array();
$cache_post_metas['post-1']['thumbnail']['thumb'] = 'http://xxx.com/xx.jpg';
....

上面那个例子，是不是略显蛋疼。有没有一种科学点的方法来判断和赋值呢？

thumbnail

isset

赋值

4 replies • 2014-06-30 12:28:30 +08:00

lizheming

Jun 30, 2014

如果是PHP的话，这种情况下完全不需要判断吧？

kmvan

Jun 30, 2014

为啥不需要判断呢？

issac

Jun 30, 2014

直接赋值,PHP会根据情况创建数组的:
$cache_post_metas['post-1']['thumbnail']['thumb'] = 'http://xxx.com/xx.jpg';

如果是要输出,就需要先判断
if(isset($cache_post_metas['post-1']['thumbnail']['thumb'])) {
echo $cache_post_metas['post-1']['thumbnail']['thumb'];
}

kmvan

Jun 30, 2014

$cache_post_metas['post-1']['thumbnail']['thumb'] = 'http://xxx.com/xx.jpg';

这样子的话，php会提示下标['post-1']未定义的警告哦。。