Function Reference/add option

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Description

A safe way of adding a named option/value pair to the options database table. It does nothing if the option already exists. After the option is saved, it can be accessed with get_option(), changed with update_option(), and deleted with delete_option().

You do not need to serialize values. If the value needs to be serialized, then it will be serialized before it is inserted into the database. You can create options without values and then add values later.

Calling add_option first checks whether the option has already been added, and returns false if an option with the same name exists. Next, it checks to make sure the option name is not one of the protected names alloptions or notoptions, and dies with an error message if attempting to overwrite a protected option. If the option name is not protected, and does not already exist, the option will be created.

Note: add_option uses get_option to determine whether the option already exists, and since get_option returns false as the default value, if you set an option to false in the database (e.g. via update_option($option_name, false)), then a subsequent call to add_option will change the value, because it will seem to add_option that the option does not exist.

vs. update_option()

If you are trying to ensure that a given option is created, use update_option() instead, which bypasses the option name check and updates the option with the desired value whether or not it exists.

NB: you cannot specify autoload='no' if you use update_option(). If you need to specify autoload='no', and you are not sure whether the option already exists, then call delete_option() first before calling add_option().

Usage

%%%<?php add_option( $option, $value, $deprecated, $autoload ); ?>%%%

Parameters

tt$option/tt
(string) (required) Name of the option to be added. Use underscores to separate words, and do not use uppercase—this is going to be placed into the database.
Default: Nonenoinclude

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Notes

This template is for standardizing how parameters look in the Function Reference and in Template Tags. Here is an example of this template being called: prenowiki检查到模板循环:模板:Parameter/nowiki/pre 检查到模板循环:模板:Parameter

The usage of this template is below: prenowiki检查到模板循环:模板:Parameter/nowiki/pre Let's take a closer look at the parameters..

name
The name of the parameter.
datatype
The datatype that should be given for this parameter when called.
  • string
  • integer
  • boolean
  • mixed
description
A short description of the parameter.
importance
Set this parameter to optional if the parameter is optional. Otherwise, do not declare this parameter—it defaults to required.
  • required
  • optional
default
If this parameter is optional, ttdefault/tt is the value that will be used if the parameter is not declared.

wordpress.org.cn /div /noinclude

tt$value/tt
(mixed) (optional) Value for this option name. Limited to 2^32 bytes of data
Default: Empty stringnoinclude

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Notes

This template is for standardizing how parameters look in the Function Reference and in Template Tags. Here is an example of this template being called: prenowiki检查到模板循环:模板:Parameter/nowiki/pre 检查到模板循环:模板:Parameter

The usage of this template is below: prenowiki检查到模板循环:模板:Parameter/nowiki/pre Let's take a closer look at the parameters..

name
The name of the parameter.
datatype
The datatype that should be given for this parameter when called.
  • string
  • integer
  • boolean
  • mixed
description
A short description of the parameter.
importance
Set this parameter to optional if the parameter is optional. Otherwise, do not declare this parameter—it defaults to required.
  • required
  • optional
default
If this parameter is optional, ttdefault/tt is the value that will be used if the parameter is not declared.

wordpress.org.cn /div /noinclude

tt$deprecated/tt
(string) (optional) Deprecated in WordPress Version 2.3.
Default: Empty stringnoinclude

div class=template-description style=padding: 0 1.5em; border: 1px solid #eeeeee; background-color: #f9f9f9

Notes

This template is for standardizing how parameters look in the Function Reference and in Template Tags. Here is an example of this template being called: prenowiki检查到模板循环:模板:Parameter/nowiki/pre 检查到模板循环:模板:Parameter

The usage of this template is below: prenowiki检查到模板循环:模板:Parameter/nowiki/pre Let's take a closer look at the parameters..

name
The name of the parameter.
datatype
The datatype that should be given for this parameter when called.
  • string
  • integer
  • boolean
  • mixed
description
A short description of the parameter.
importance
Set this parameter to optional if the parameter is optional. Otherwise, do not declare this parameter—it defaults to required.
  • required
  • optional
default
If this parameter is optional, ttdefault/tt is the value that will be used if the parameter is not declared.

wordpress.org.cn /div /noinclude

tt$autoload/tt
(string) (optional) Should this option be automatically loaded by the function wp_load_alloptions() (puts options into object cache on each page load)? Valid values: yes or no.
Default: yesnoinclude

div class=template-description style=padding: 0 1.5em; border: 1px solid #eeeeee; background-color: #f9f9f9

Notes

This template is for standardizing how parameters look in the Function Reference and in Template Tags. Here is an example of this template being called: prenowiki检查到模板循环:模板:Parameter/nowiki/pre 检查到模板循环:模板:Parameter

The usage of this template is below: prenowiki检查到模板循环:模板:Parameter/nowiki/pre Let's take a closer look at the parameters..

name
The name of the parameter.
datatype
The datatype that should be given for this parameter when called.
  • string
  • integer
  • boolean
  • mixed
description
A short description of the parameter.
importance
Set this parameter to optional if the parameter is optional. Otherwise, do not declare this parameter—it defaults to required.
  • required
  • optional
default
If this parameter is optional, ttdefault/tt is the value that will be used if the parameter is not declared.

wordpress.org.cn /div /noinclude

Return Value

tt/tt
tt style=color:gray@return/tt (boolean) tt style=color:blue/tt: False if option was not added and true if option was addednoinclude

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Description

This template is for standardizing how return values look in the Function Reference and in Template Tags.

Parameters

(1|param|param)
Return param or value (also can be: null, void...).
(2|datatype|datatype)
Datatype of return value.
(3|description|description)
Description of return value.

Usage

prenowiki检查到模板循环:模板:Return/nowiki/pre

Example

prenowiki检查到模板循环:模板:Return/nowiki/pre

Output

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Example

<?php add_option( 'myhack_extraction_length', '255', '', 'yes' ); ?>

Change Log

Since: 1.0.0

Source File

add_option() is located in onlyincludecodewp-includes/option.php/code/onlyinclude

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Template Description

Link to the source code on http://core.trac.wordpress.org/browser/.

Parameters

  1. filename
  2. (option) path to codetag/code (version) or codetrunk/code. This option is only used for a new function.br /Default: codetrunk/code -- trunk is the latest bleeding edge development version of WordPress.

Usage

Link to the stable version: pre检查到模板循环:模板:Trac/pre

Link to trunk: pre检查到模板循环:模板:Trac/pre

/div

wordpress.org.cn.

Related

Options API: get_option, add_option, update_option, delete_option

includeonlydiv style=clear:both; background-color:#F7F7F7; border:1px solid #CCCCCC; color:#000000; padding:7px; margin:0.5em auto 0.5em auto; vertical-align:middle;See also index of Function Reference and index of Template Tags./div/includeonlynoinclude

Description

This Template is used by Codex:Template Messages.

Usage

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Result

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/noinclude