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paramName
( optional enumerated Type array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
Parameters

Google Chrome Extensions (Labs)

chrome.extension

The chrome.extension module has utilities that can be used by any extension page. It includes support for exchanging messages between an extension and its content scripts or between extensions, as described in detail in Message Passing.

Support for content scripts

Unlike the other chrome.* APIs, parts of chrome.extension can be used by content scripts:

sendRequest() and onRequest
Simple communication with extension pages
connect() and onConnect
Extended communication with extension pages
getURL()
Access to extension resources such as image files

For details, see Content Scripts.

API reference: chrome.extension

Properties

lastError

chrome.extension.lastError
lastError
( optional Type array of object )
Set for the lifetime of a callback if an ansychronous extension api has resulted in an error. If no error has occured lastError will be undefined.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
message
( Type array of string )
Description of the error that has taken place.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

inIncognitoContext

chrome.extension.inIncognitoContext
inIncognitoContext
( optional Type array of object )
True for content scripts running inside incognito tabs, and for extension pages running inside an incognito process. The latter only applies to extensions with 'split' incognito_behavior.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
message
( Type array of boolean )
True if the page or script is in an incongito process.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Methods

connect

Port chrome.extension.connect(, string extensionId, object connectInfo)

Attempts to connect to other listeners within the extension (such as the extension's background page). This is primarily useful for content scripts connecting to their extension processes. Extensions may connect to content scripts embedded in tabs via chrome.tabs.connect().

Parameters

extensionId
( optional Type array of string )
The extension ID of the extension you want to connect to. If omitted, default is your own extension.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
connectInfo
( optional Type array of object )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
name
( optional Type array of string )
Will be passed into onConnect for extension processes that are listening for the connection event.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

paramName
( Port array of paramType )
Port through which messages can be sent and received with the extension. The port's onDisconnect event is fired if extension does not exist.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(Type param1, Type param2) {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

getBackgroundPage

DOMWindow chrome.extension.getBackgroundPage(, )

Returns the JavaScript 'window' object for the background page running inside the current extension. Returns null if the extension has no background page.

Parameters

Returns

paramName
( Type array of DOMWindow )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(Type param1, Type param2) {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

getURL

string chrome.extension.getURL(, string path)

Converts a relative path within an extension install directory to a fully-qualified URL.

Parameters

path
( Type array of string )
A path to a resource within an extension expressed relative to its install directory.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

paramName
( Type array of string )
The fully-qualified URL to the resource.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(Type param1, Type param2) {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

getViews

array of DOMWindow chrome.extension.getViews(, object fetchProperties)

Returns an array of the JavaScript 'window' objects for each of the pages running inside the current extension.

Parameters

fetchProperties
( optional Type array of object )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
type
( optional enumerated Type array of string ["tab", "infobar", "notification", "popup"] )
The type of view to get. If omitted, returns all views (including background pages and tabs). Valid values: 'tab', 'infobar', 'notification', 'popup'.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
windowId
( optional Type array of integer )
The window to restrict the search to. If omitted, returns all views.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

paramName
( Type array of Type array of DOMWindow paramType )
Array of global objects
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(Type param1, Type param2) {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

isAllowedFileSchemeAccess

void chrome.extension.isAllowedFileSchemeAccess(, function callback)

Retrieves the state of the extension's access to the 'file://' scheme (as determined by the user-controlled 'Allow access to File URLs' checkbox.

Parameters

callback
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(boolean isAllowedAccess) {...};
isAllowedAccess
( Type array of boolean )
True if the extension can access the 'file://' scheme, false otherwise.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

This function was added in version 12.0.706.0. If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

isAllowedIncognitoAccess

void chrome.extension.isAllowedIncognitoAccess(, function callback)

Retrieves the state of the extension's access to Incognito-mode (as determined by the user-controlled 'Allowed in Incognito' checkbox.

Parameters

callback
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(boolean isAllowedAccess) {...};
isAllowedAccess
( Type array of boolean )
True if the extension has access to Incognito mode, false otherwise.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

This function was added in version 12.0.706.0. If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

sendRequest

void chrome.extension.sendRequest(, string extensionId, any request, function responseCallback)

Sends a single request to other listeners within the extension. Similar to chrome.extension.connect, but only sends a single request with an optional response. The chrome.extension.onRequest event is fired in each page of the extension.

Parameters

extensionId
( optional Type array of string )
The extension ID of the extension you want to connect to. If omitted, default is your own extension.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
request
( Type array of any )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
responseCallback
( optional Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
Parameters
response
( Type array of any )
The JSON response object sent by the handler of the request. If an error occurs while connecting to the extension, the callback will be called with no arguments and chrome.extension.lastError will be set to the error message.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(any response) {...};
response
( Type array of any )
The JSON response object sent by the handler of the request. If an error occurs while connecting to the extension, the callback will be called with no arguments and chrome.extension.lastError will be set to the error message.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

setUpdateUrlData

void chrome.extension.setUpdateUrlData(, string data)

Sets the value of the ap CGI parameter used in the extension's update URL. This value is ignored for extensions that are hosted in the Chrome Extension Gallery.

Parameters

data
( Type array of string )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(Type param1, Type param2) {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Events

onConnect

chrome.extension.onConnect.addListener(function(Port port) {...});

Fired when a connection is made from either an extension process or a content script.

Parameters

port
( Port array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

onConnectExternal

chrome.extension.onConnectExternal.addListener(function(Port port) {...});

Fired when a connection is made from another extension.

Parameters

port
( Port array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

onRequest

chrome.extension.onRequest.addListener(function(any request, MessageSender sender, function sendResponse) {...});

Fired when a request is sent from either an extension process or a content script.

Parameters

request
( Type array of any )
The request sent by the calling script.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
sender
( MessageSender array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
sendResponse
( Type array of function )
Function to call when you have a response. The argument should be any JSON-ifiable object, or undefined if there is no response.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

onRequestExternal

chrome.extension.onRequestExternal.addListener(function(any request, MessageSender sender, function sendResponse) {...});

Fired when a request is sent from another extension.

Parameters

request
( Type array of any )
The request sent by the calling script.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
sender
( MessageSender array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
sendResponse
( Type array of function )
Function to call when you have a response. The argument should be any JSON-ifiable object, or undefined if there is no response.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Types

MessageSender

paramName
( Type array of object )
An object containing information about the script context that sent a message or request.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
tab
( optional Tab array of paramType )
This property will only be present when the connection was opened from a tab or content script.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
id
( Type array of string )
The extension ID of the extension that opened the connection.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Event

paramName
( Type array of object )
An object which allows the addition and removal of listeners for a Chrome event.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
addListener
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
removeListener
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
hasListener
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
hasListeners
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Port

paramName
( Type array of object )
An object which allows two way communication with other pages.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
name
( Type array of string )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
onDisconnect
( Event array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
onMessage
( Event array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
postMessage
( Type array of function )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
sender
( optional MessageSender array of paramType )
This property will only be present on ports passed to onConnect/onConnectExternal listeners.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.