(PECL apc >= 3.0.0)
apc_define_constants — Defines a set of constants for retrieval and mass-definition
$key
, array $constants
[, bool $case_sensitive = true
] )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).
key
The key serves as the name of the constant set
being stored. This key is used to retrieve the
stored constants in apc_load_constants().
constantsAn 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 FALSE the
constants will be declared as case-insensitive symbols.
成功时返回 TRUE， 或者在失败时返回 FALSE。
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