apc_define_constants
(PECL apc >= 3.0.0)
apc_define_constants — Defines a set of constants for retrieval and mass-definition
说明
$key ,
array $constants [,
bool $case_sensitive = TRUE ] ) :
bool
define() is notoriously slow. Since the main benefit of APC is to increase the performance of scripts/applications, this mechanism is provided to streamline the process of mass constant definition. However, this function does not perform as well as anticipated.
For a better-performing solution, try the » hidef extension from PECL.
Note: To remove a set of stored constants (without clearing the entire cache), an empty array may be passed as the
constantsparameter, effectively clearing the stored value(s).
参数
-
key -
The
keyserves as the name of the constant set being stored. Thiskeyis used to retrieve the stored constants in apc_load_constants(). -
constants -
An associative array of constant_name => value pairs. The constant_name must follow the normal constant naming rules. value must evaluate to a scalar value.
-
case_sensitive -
The default behaviour for constants is to be declared case-sensitive; i.e. CONSTANT and Constant represent different values. If this parameter evaluates to
FALSEthe constants will be declared as case-insensitive symbols.
返回值
成功时返回 TRUE， 或者在失败时返回 FALSE。
范例
Example #1 apc_define_constants() example
<?php
$constants = array(
'ONE' => 1,
'TWO' => 2,
'THREE' => 3,
);
apc_define_constants('numbers', $constants);
echo ONE, TWO, THREE;
?>
以上例程会输出：
123
参见
- apc_load_constants() - Loads a set of constants from the cache
- define() - 定义一个常量
- constant() - 返回一个常量的值
- Or the PHP constants reference
