(PECL uopz 1, PECL uopz 2, PECL uopz 5, PECL uopz 6)
uopz_undefine — Undefine a constant
$constant
) : bool$class
, string $constant
) : boolRemoves the constant at runtime
class
The name of the class containing constant
constant
The name of an existing constant
成功时返回 TRUE
, 或者在失败时返回 FALSE
。
Example #1 uopz_undefine() example
<?php
define("MY", true);
uopz_undefine("MY");
var_dump(defined("MY"));
?>
以上例程会输出:
bool(false)