本文介绍了php 为空时为空?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
I have a question regarding NULL in PHP:
$a = '';
if($a == NULL) {
echo 'is null';
}
Why do I see is null when $a is an empty string? Is that a bug?
解决方案
What you're looking for is:
if($variable === NULL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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