# Memcache::replace

(PECL memcache:0.2-2.1.2)

Memcache::replace — Replace value of the existing item

### Description

bool Memcache::replace ( string `$key` , mixed `$var` [, int `$flag` [, int `$expire` ]] )

Memcache::replace() should be used to replace value of existing item with `key` . In case if item with such key doesn't exists, Memcache::replace() returns `FALSE`. For the rest Memcache::replace() behaves similarly to Memcache::set(). Also you can use memcache_replace() function.

### Parameters

`key`

  The key that will be associated with the item.

`var`

  The variable to store. Strings and integers are stored as is, other types are stored serialized.

`flag`

  Use `MEMCACHE_COMPRESSED` to store the item compressed (uses zlib).

`expire`

  Expiration time of the item. If it's equal to zero, the item will never expire. You can also use Unix timestamp or a number of seconds starting from current time, but in the latter case the number of seconds may not exceed 2592000 (30 days).

### Return Values

Returns `TRUE` on success or `FALSE` on failure.

### Examples

Example#1 Memcache::replace() example

`<?php
$memcache_obj = memcache_connect('memcache_host', 11211);
/* procedural API */
memcache_replace($memcache_obj, "test_key", "some variable", false, 30);
/* OO API */
$memcache_obj->replace("test_key", "some variable", false, 30);
?>`

### See Also

- Memcache::set()
- Memcache::add()