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李二狗 — @Meniny
Published 12:01 Jan 21, 2012.
Created by @ezra. Categorized in #Programming, and tagged as #PHP.
Source format: Markdown
空类型 NULL 对大小写不敏感，这种类型只有一个取值，表示一个变量没有值，当被赋值为 NULL 或未被赋值、又或被调用 unset()，则变量被认定为NULL。
<?php
$ivar = 'meniny';
var_dump($ivar);
$ivar = null;
var_dump($ivar);
?>
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