apc_dec

(PECL apc >= 3.1.1)

apc_dec — Decrease a stored number

说明

int apc_dec ( string $key [, int $step = 1 [, bool &$success ]] )

Decreases a stored integer value.

参数

key: The key of the value being decreased.
step: The step, or value to decrease.
success: Optionally pass the success or fail boolean value to this referenced variable.

返回值

Returns the current value of key's value on success, 或者在失败时返回 FALSE

范例

Example #1 apc_dec() example

  <?php
 echo  "Let's do something with success" ,  PHP_EOL ;

 apc_store ( 'anumber' ,  42 );

echo  apc_fetch ( 'anumber' ),  PHP_EOL ;

echo  apc_dec ( 'anumber' ),  PHP_EOL ;
echo  apc_dec ( 'anumber' ,  10 ),  PHP_EOL ;
echo  apc_dec ( 'anumber' ,  10 ,  $success ),  PHP_EOL ;

 var_dump ( $success );

echo  "Now, let's fail" ,  PHP_EOL ,  PHP_EOL ;

 apc_store ( 'astring' ,  'foo' );

 $ret  =  apc_dec ( 'astring' ,  1 ,  $fail );

 var_dump ( $ret );
 var_dump ( $fail );
 ?>

以上例程的输出类似于：

Let's do something with success
42
41
31
21
bool(true)Now, let's fail
bool(false)
bool(false)

参见

apc_inc() - 递增一个储存的数字

用户评论:

[#1] elfi47 [2012-10-20 16:32:12]

check for errors with === FALSE or === 0

dec() will increase to 3, 2, 1, 0, -1, -2, -3....

if you check with == FALSE you will get an wrong FALSE result if the variable is on 0.