# wincache_ucache_cas

(PECL wincache >= 1.1.0)

wincache_ucache_cas — Compares the variable with old value and assigns new value to it

### 说明

wincache_ucache_cas ( string `$key` , int `$old_value` , int `$new_value` ) : bool

Compares the variable associated with the `key` with `old_value` and if it matches then assigns the `new_value` to it.

### 参数

`key`

  The `key` that is used to store the variable in the cache. `key` is case sensitive.

`old_value`

  Old value of the variable pointed by `key` in the user cache. The value should be of type long, otherwise the function returns `FALSE`.

`new_value`

  New value which will get assigned to variable pointer by `key` if a match is found. The value should be of type long, otherwise the function returns `FALSE`.

### 返回值

成功时返回 `TRUE`， 或者在失败时返回 `FALSE`。

### 范例

Example #1 Using wincache_ucache_cas()

    <?php
    wincache_ucache_set('counter', 2922);
    var_dump(wincache_ucache_cas('counter', 2922, 1));
    var_dump(wincache_ucache_get('counter'));
    ?>

以上例程会输出：

    bool(true)
    int(1)

### 参见

- wincache_ucache_inc() - Increments the value associated with the key
- wincache_ucache_dec() - Decrements the value associated with the key