文字
apcu_cas
(PECL apcu >= 4.0.0)
apcu_cas — Updates an old value with a new value
说明
bool apcu_cas
( string
$key
, int $old
, int $new
) apcu_cas() updates an already existing integer value if the
old parameter matches the currently stored value
with the value of the new parameter.
参数
-
key -
The key of the value being updated.
-
old -
The old value (the value currently stored).
-
new -
The new value to update to.
返回值
成功时返回 TRUE ， 或者在失败时返回 FALSE 。
范例
Example #1 apcu_cas() example
<?php
apcu_store ( 'foobar' , 2 );
echo '$foobar = 2' , PHP_EOL ;
echo '$foobar == 1 ? 2 : 1 = ' , ( apcu_cas ( 'foobar' , 1 , 2 ) ? 'ok' : 'fail' ), PHP_EOL ;
echo '$foobar == 2 ? 1 : 2 = ' , ( apcu_cas ( 'foobar' , 2 , 1 ) ? 'ok' : 'fail' ), PHP_EOL ;
echo '$foobar = ' , apcu_fetch ( 'foobar' ), PHP_EOL ;
echo '$f__bar == 1 ? 2 : 1 = ' , ( apcu_cas ( 'f__bar' , 1 , 2 ) ? 'ok' : 'fail' ), PHP_EOL ;
apcu_store ( 'perfection' , 'xyz' );
echo '$perfection == 2 ? 1 : 2 = ' , ( apcu_cas ( 'perfection' , 2 , 1 ) ? 'ok' : 'epic fail' ), PHP_EOL ;
echo '$foobar = ' , apcu_fetch ( 'foobar' ), PHP_EOL ;
?> 以上例程的输出类似于：
$foobar = 2 $foobar == 1 ? 2 : 1 = fail $foobar == 2 ? 1 : 2 = ok $foobar = 1 $f__bar == 1 ? 2 : 1 = fail $perfection == 2 ? 1 : 2 = epic fail $foobar = 1
参见
- apcu_dec() - Decrease a stored number
- apcu_store() - Cache a variable in the data store