# Memcached::increment

(PECL memcached >= 0.1.0)

Memcached::increment — Increment numeric item's value

### Description

public Memcached::increment ( string `$key` [, int `$offset` = 1 [, int `$initial_value` = 0 [, int `$expiry` = 0 ]]] ) : int

Memcached::increment() increments a numeric item's value by the specified `offset`. If the item's value is not numeric, an error will result. Memcached::increment() will set the item to the `initial_value` parameter if the key doesn't exist.

### Parameters

`key`

  The key of the item to increment.

`offset`

  The amount by which to increment the item's value.

`initial_value`

  The value to set the item to if it doesn't currently exist.

`expiry`

  The expiry time to set on the item.

### Return Values

Returns new item's value on success or `FALSE` on failure.

### Examples

Example #1 Memcached::increment() example

`<?php
$m = new Memcached();
$m->addServer('localhost', 11211);
$m->set('counter', 0);
$m->increment('counter');
$n = $m->increment('counter', 10);
var_dump($n);
$m->set('counter', 'abc');
$n = $m->increment('counter');
// ^ will fail due to item value not being numeric
var_dump($n);
?>`

The above example will output:

    int(11)
    bool(false)

### See Also

- Memcached::decrement() - Decrement numeric item's value
- Memcached::decrementByKey() - Decrement numeric item's value, stored on a specific server
- Memcached::incrementByKey() - Increment numeric item's value, stored on a specific server