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uopz_undefine

(PECL uopz 1, PECL uopz 2, PECL uopz 5, PECL uopz 6, PECL uopz 7)

uopz_undefine — Undefine a constant

说明

uopz_undefine(string $constant): bool
uopz_undefine(string $class, string $constant): bool

Removes the constant at runtime

参数

class

The name of the class containing constant

constant

The name of an existing constant

返回值

成功时返回 true， 或者在失败时返回 false。

示例

示例 #1 uopz_undefine() example

<?php
define("MY", true);

uopz_undefine("MY");

var_dump(defined("MY"));
?>

以上示例会输出：

bool(false)