# wincache_ucache_set

(PECL wincache >= 1.1.0)

wincache_ucache_set — Adds a variable in user cache and overwrites a variable if it already exists in the cache

### 说明

wincache_ucache_set ( mixed `$key` , mixed `$value` [, int `$ttl` = 0 ] ) : bool
wincache_ucache_set ( array `$values` [, mixed `$unused` = NULL [, int `$ttl` = 0 ]] ) : bool

Adds a variable in user cache. Overwrites a variable if it already exists in the cache. The added or updated variable remains in the user cache unless its time to live expires or it is deleted by using wincache_ucache_delete() or wincache_ucache_clear() functions.

### 参数

`key`

  Store the variable using this `key` name. If a variable with same `key` is already present the function will overwrite the previous value with the new one. `key` is case sensitive. `key` can also take array of name => value pairs where names will be used as keys. This can be used to add multiple values in the cache in one operation, thus avoiding race condition.

`value`

  Value of a variable to store. `Value` supports all data types except resources, such as file handles. This paramter is ignored if first argument is an array. A general guidance is to pass `NULL` as `value` while using array as `key`. If `value` is an object, or an array containing objects, then the objects will be serialized. See __sleep() for details on serializing objects.

`values`

  Associative array of keys and values.

`ttl`

  Time for the variable to live in the cache in seconds. After the value specified in `ttl` has passed the stored variable will be deleted from the cache. This parameter takes a default value of 0 which means the variable will stay in the cache unless explicitly deleted by using wincache_ucache_delete() or wincache_ucache_clear() functions.

### 返回值

If `key` is string, the function returns `TRUE` on success and `FALSE` on failure.

If `key` is an array, the function returns:

- If all the name => value pairs in the array can be set, function returns an empty array;
- If all the name => value pairs in the array cannot be set, function returns `FALSE`;
- If some can be set while others cannot, function returns an array with name=>value pair for which the addition failed in the user cache.

### 范例

Example #1 wincache_ucache_set() with `key` as a string

    <?php
    $bar = 'BAR';
    var_dump(wincache_ucache_set('foo', $bar));
    var_dump(wincache_ucache_get('foo'));
    $bar1 = 'BAR1';
    var_dump(wincache_ucache_set('foo', $bar1));
    var_dump(wincache_ucache_get('foo'));
    ?>

以上例程会输出：

    bool(true)
    string(3) "BAR"
    bool(true)
    string(3) "BAR1"

Example #2 wincache_ucache_set() with `key` as an array

    <?php
    $colors_array = array('green' => '5', 'Blue' => '6', 'yellow' => '7', 'cyan' => '8');
    var_dump(wincache_ucache_set($colors_array));
    var_dump(wincache_ucache_set($colors_array));
    var_dump(wincache_ucache_get('Blue'));
    ?>

以上例程会输出：

    array(0) {}
    array(0) {}
    string(1) "6"

### 参见

- wincache_ucache_add() - Adds a variable in user cache only if variable does not already exist in the cache
- wincache_ucache_get() - Gets a variable stored in the user cache
- wincache_ucache_delete() - Deletes variables from the user cache
- wincache_ucache_clear() - Deletes entire content of the user cache
- wincache_ucache_exists() - Checks if a variable exists in the user cache
- wincache_ucache_meminfo() - Retrieves information about user cache memory usage
- wincache_ucache_info() - Retrieves information about data stored in the user cache
- __sleep()