Adobe® Flex® 4 Language Reference
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flash.net 
SharedObject 
Packageflash.net
Classpublic class SharedObject
InheritanceSharedObject Inheritance EventDispatcher Inheritance Object

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The SharedObject class is used to read and store limited amounts of data on a user's computer or on a server. Shared objects offer real-time data sharing between multiple client SWF files and objects that are persistent on the local computer or remote server. Local shared objects are similar to browser cookies and remote shared objects are similar to real-time data transfer devices. To use remote shared objects, you need Adobe Flash Media Server.

Use shared objects to do the following:

  • Maintain local persistence. This is the simplest way to use a shared object, and does not require Flash Media Server. For example, you can call SharedObject.getLocal() to create a shared object in an application, such as a calculator with memory. When the user closes the calculator, Flash Player saves the last value in a shared object on the user's computer. The next time the calculator is run, it contains the values it had previously. Alternatively, if you set the shared object's properties to null before the calculator application is closed, the next time the application runs, it opens without any values. Another example of maintaining local persistence is tracking user preferences or other data for a complex website, such as a record of which articles a user read on a news site. Tracking this information allows you to display articles that have already been read differently from new, unread articles. Storing this information on the user's computer reduces server load.
  • Store and share data on Flash Media Server. A shared object can store data on the server for other clients to retrieve. For example, call SharedObject.getRemote() to create a remote shared object, such as a phone list, that is persistent on the server. Whenever a client makes changes to the shared object, the revised data is available to all clients currently connected to the object or who later connect to it. If the object is also persistent locally, and a client changes data while not connected to the server, the data is copied to the remote shared object the next time the client connects to the object.
  • Share data in real time. A shared object can share data among multiple clients in real time. For example, you can open a remote shared object that stores a list of users connected to a chat room that is visible to all clients connected to the object. When a user enters or leaves the chat room, the object is updated and all clients that are connected to the object see the revised list of chat room users.

To create a local shared object, call SharedObject.getLocal(). To create a remote shared object, call SharedObject.getRemote().

When an application closes, shared objects are flushed, or written to a disk. You can also call the flush() method to explicitly write data to a disk.

Local disk space considerations. Local shared objects have some limitations that are important to consider as you design your application. Sometimes SWF files may not be allowed to write local shared objects, and sometimes the data stored in local shared objects can be deleted without your knowledge. Flash Player users can manage the disk space that is available to individual domains or to all domains. When users decrease the amount of disk space available, some local shared objects may be deleted. Flash Player users also have privacy controls that can prevent third-party domains (domains other than the domain in the current browser address bar) from reading or writing local shared objects.

Note: SWF files that are stored and run on a local computer, not from a remote server, can always write third-party shared objects to disk. For more information about third-party shared objects, see the Global Storage Settings panel in Flash Player Help.

It's a good idea to check for failures related to the amount of disk space and to user privacy controls. Perform these checks when you call getLocal() and flush():

  • SharedObject.getLocal() — Flash Player throws an exception when a call to this method fails, such as when the user has disabled third-party shared objects and the domain of your SWF file does not match the domain in the browser address bar.
  • SharedObject.flush() — Flash Player throws an exception when a call to this method fails. It returns SharedObjectFlushStatus.FLUSHED when it succeeds. It returns SharedObjectFlushStatus.PENDING when additional storage space is needed. Flash Player prompts the user to allow an increase in storage space for locally saved information. Thereafter, the netStatus event is dispatched with an information object indicating whether the flush failed or succeeded.

If your SWF file attempts to create or modify local shared objects, make sure that your SWF file is at least 215 pixels wide and at least 138 pixels high (the minimum dimensions for displaying the dialog box that prompts users to increase their local shared object storage limit). If your SWF file is smaller than these dimensions and an increase in the storage limit is required, SharedObject.flush() fails, returning SharedObjectFlushedStatus.PENDING and dispatching the netStatus event.

Remote shared objects. With Flash Media Server, you can create and use remote shared objects, that are shared in real-time by all clients connected to your application. When one client changes a property of a remote shared object, the property is changed for all connected clients. You can use remote shared objects to synchronize clients, for example, users in a multi-player game.

Each remote shared object has a data property which is an Object with properties that store data. Call setProperty() to change an property of the data object. The server updates the properties, dispatches a sync event, and sends the properties back to the connected clients.

You can choose to make remote shared objects persistent on the client, the server, or both. By default, Flash Player saves locally persistent remote shared objects up to 100K in size. When you try to save a larger object, Flash Player displays the Local Storage dialog box, which lets the user allow or deny local storage for the shared object. Make sure your Stage size is at least 215 by 138 pixels; this is the minimum size Flash requires to display the dialog box.

If the user selects Allow, the server saves the shared object and dispatches a netStatus event with a code property of SharedObject.Flush.Success. If the user select Deny, the server does not save the shared object and dispatches a netStatus event with a code property of SharedObject.Flush.Failed.

View the examples

See also



Public Properties
 PropertyDefined By
  client : Object
Indicates the object on which callback methods are invoked.
SharedObject
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  data : Object
[read-only] The collection of attributes assigned to the data property of the object; these attributes can be shared and stored.
SharedObject
  defaultObjectEncoding : uint
[static] The default object encoding (AMF version) for all local shared objects created in the SWF file.
SharedObject
  fps : Number
[write-only] Specifies the number of times per second that a client's changes to a shared object are sent to the server.
SharedObject
  objectEncoding : uint
The object encoding (AMF version) for this shared object.
SharedObject
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
  size : uint
[read-only] The current size of the shared object, in bytes.
SharedObject
Public Methods
 MethodDefined By
 Inherited
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event.
EventDispatcher
  
For local shared objects, purges all of the data and deletes the shared object from the disk.
SharedObject
  
Closes the connection between a remote shared object and the server.
SharedObject
  
connect(myConnection:NetConnection, params:String = null):void
Connects to a remote shared object on a server through a specified NetConnection object.
SharedObject
 Inherited
Dispatches an event into the event flow.
EventDispatcher
  
flush(minDiskSpace:int = 0):String
Immediately writes a locally persistent shared object to a local file.
SharedObject
  
getLocal(name:String, localPath:String = null, secure:Boolean = false):SharedObject
[static] Returns a reference to a locally persistent shared object that is only available to the current client.
SharedObject
  
getRemote(name:String, remotePath:String = null, persistence:Object = false, secure:Boolean = false):SharedObject
[static] Returns a reference to a shared object on Flash Media Server that multiple clients can access.
SharedObject
 Inherited
Checks whether the EventDispatcher object has any listeners registered for a specific type of event.
EventDispatcher
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object.
EventDispatcher
  
send(... arguments):void
Broadcasts a message to all clients connected to a remote shared object, including the client that sent the message.
SharedObject
  
setDirty(propertyName:String):void
Indicates to the server that the value of a property in the shared object has changed.
SharedObject
  
setProperty(propertyName:String, value:Object = null):void
Updates the value of a property in a shared object and indicates to the server that the value of the property has changed.
SharedObject
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
 Inherited
Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.
EventDispatcher
Events
 Event Summary Defined By
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.EventDispatcher
  Dispatched when an exception is thrown asynchronously — that is, from native asynchronous code.SharedObject
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.EventDispatcher
  Dispatched when a SharedObject instance is reporting its status or error condition.SharedObject
  Dispatched when a remote shared object has been updated by the server.SharedObject
Property Detail

client

property
client:Object

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Indicates the object on which callback methods are invoked. The default object is this. You can set the client property to another object, and callback methods will be invoked on that other object.



Implementation
    public function get client():Object
    public function set client(value:Object):void

Throws
TypeError — The client property must be set to a non-null object.

data

property 
data:Object  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The collection of attributes assigned to the data property of the object; these attributes can be shared and stored. Each attribute can be an object of any ActionScript or JavaScript type — Array, Number, Boolean, ByteArray, XML, and so on. For example, the following lines assign values to various aspects of a shared object:

     var items_array:Array = new Array(101, 346, 483);
     var currentUserIsAdmin:Boolean = true;
     var currentUserName:String = "Ramona";
     
     var my_so:SharedObject = SharedObject.getLocal("superfoo");
     my_so.data.itemNumbers = items_array;
     my_so.data.adminPrivileges = currentUserIsAdmin;
     my_so.data.userName = currentUserName;
     
     for (var prop in my_so.data) {
       trace(prop+": "+my_so.data[prop]);
     }
     

All attributes of a shared object's data property are saved if the object is persistent, and the shared object contains the following information:

     userName: Ramona
     adminPrivileges: true
     itemNumbers: 101,346,483
     

Note: Do not assign values directly to the data property of a shared object, as in so.data = someValue; Flash Player ignores these assignments.

To delete attributes for local shared objects, use code such as delete so.data.attributeName; setting an attribute to null or undefined for a local shared object does not delete the attribute.

To create private values for a shared object — values that are available only to the client instance while the object is in use and are not stored with the object when it is closed — create properties that are not named data to store them, as shown in the following example:

     var my_so:SharedObject = SharedObject.getLocal("superfoo");
     my_so.favoriteColor = "blue";
     my_so.favoriteNightClub = "The Bluenote Tavern";
     my_so.favoriteSong = "My World is Blue";
     
     for (var prop in my_so) {
       trace(prop+": "+my_so[prop]);
     }
     

The shared object contains the following data:

     favoriteSong: My World is Blue
     favoriteNightClub: The Bluenote Tavern
     favoriteColor: blue
     data: [object Object]
     

For remote shared objects used with a server, all attributes of the data property are available to all clients connected to the shared object, and all attributes are saved if the object is persistent. If one client changes the value of an attribute, all clients now see the new value.



Implementation
    public function get data():Object

See also

defaultObjectEncoding

property 
defaultObjectEncoding:uint

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The default object encoding (AMF version) for all local shared objects created in the SWF file. When local shared objects are written to disk, the SharedObject.defaultObjectEncoding property indicates which Action Message Format version should be used: the ActionScript 3.0 format (AMF3) or the ActionScript 1.0 or 2.0 format (AMF0).

For more information about object encoding, including the difference between encoding in local and remote shared objects, see the description of the objectEncoding property.

The default value of SharedObject.defaultObjectEncoding is set to use the ActionScript 3.0 format, AMF3. If you need to write local shared objects that ActionScript 2.0 or 1.0 SWF files can read, set SharedObject.defaultObjectEncoding to use the ActionScript 1.0 or ActionScript 2.0 format, flash.net.ObjectEncoding.AMF0, at the beginning of your script, before you create any local shared objects. All local shared objects created thereafter will use AMF0 encoding and can interact with older content. You cannot change the objectEncoding value of existing local shared objects by setting SharedObject.defaultObjectEncoding after the local shared objects have been created.

To set the object encoding on a per-object basis, rather than for all shared objects created by the SWF file, set the objectEncoding property of the local shared object instead.



Implementation
    public static function get defaultObjectEncoding():uint
    public static function set defaultObjectEncoding(value:uint):void

See also

fps

property 
fps:Number  [write-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Specifies the number of times per second that a client's changes to a shared object are sent to the server.

Use this method when you want to control the amount of traffic between the client and the server. For example, if the connection between the client and server is relatively slow, you may want to set fps to a relatively low value. Conversely, if the client is connected to a multiuser application in which timing is important, you may want to set fps to a relatively high value.

Setting fps will trigger a sync event and update all changes to the server. If you only want to update the server manually, set fps to 0.

Changes are not sent to the server until the sync event has been dispatched. That is, if the response time from the server is slow, updates may be sent to the server less frequently than the value specified in this property.



Implementation
    public function set fps(value:Number):void

objectEncoding

property 
objectEncoding:uint

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The object encoding (AMF version) for this shared object. When a local shared object is written to disk, the objectEncoding property indicates which Action Message Format version should be used: the ActionScript 3.0 format (AMF3) or the ActionScript 1.0 or 2.0 format (AMF0).

Object encoding is handled differently depending if the shared object is local or remote.

  • Local shared objects. You can get or set the value of the objectEncoding property for local shared objects. The value of objectEncoding affects what formatting is used for writing this local shared object. If this local shared object must be readable by ActionScript 2.0 or 1.0 SWF files, set objectEncoding to ObjectEncoding.AMF0. Even if object encoding is set to write AMF3, Flash Player can still read AMF0 local shared objects. That is, if you use the default value of this property, ObjectEncoding.AMF3, your SWF file can still read shared objects created by ActionScript 2.0 or 1.0 SWF files.
  • Remote shared objects. When connected to the server, a remote shared object inherits its objectEncoding setting from the associated NetConnection instance (the instance used to connect to the remote shared object). When not connected to the server, a remote shared object inherits the defaultObjectEncoding setting from the associated NetConnection instance. Because the value of a remote shared object's objectEncoding property is determined by the NetConnection instance, this property is read-only for remote shared objects.



Implementation
    public function get objectEncoding():uint
    public function set objectEncoding(value:uint):void

Throws
ReferenceError — You attempted to set the value of the objectEncoding property on a remote shared object. This property is read-only for remote shared objects because its value is determined by the associated NetConnection instance.

See also

size

property 
size:uint  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The current size of the shared object, in bytes.

Flash calculates the size of a shared object by stepping through all of its data properties; the more data properties the object has, the longer it takes to estimate its size. Estimating object size can take significant processing time, so you may want to avoid using this method unless you have a specific need for it.



Implementation
    public function get size():uint

Example  ( How to use this example )
The following code creates a SharedObject object using an id "thehobbit". A property named username is added to the data property of the SharedObject object. The size property is then traced, which returns the value indicated.

import flash.net.SharedObject;

// if these get copied or not
var mySo:SharedObject = SharedObject.getLocal("thehobbit");
mySo.data.username = "bilbobaggins";
trace(mySo.size); // 55
Method Detail

clear

()method
public function clear():void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

For local shared objects, purges all of the data and deletes the shared object from the disk. The reference to the shared object is still active, but its data properties are deleted.

For remote shared objects used with Flash Media Server, clear() disconnects the object and purges all of the data. If the shared object is locally persistent, this method also deletes the shared object from the disk. The reference to the shared object is still active, but its data properties are deleted.


Example  ( How to use this example )

The following code creates (and on subsequent executions, retrieves) a SharedObject object using an id with the value of hostName. A property named username is added to the data property of the SharedObject object. The clear() method is finally called, which wipes out all information that was added to the data object (in this case was a single property named username).

package {
    import flash.net.SharedObject;

    public class SharedObject_clear {
        private var hostName:String = "yourDomain";
        private var username:String = "yourUsername";

        public function SharedObject_clear() {
            var mySo:SharedObject = SharedObject.getLocal(hostName);
            if(mySo.data.username == null) {
                mySo.data.username = username;
                trace("set: " + mySo.data.username); // yourUsername
            }
            else {
                mySo.clear();
                trace("cleared: " + mySo.data.username); // undefined
            }
        }
    }
}

close

()method 
public function close():void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Closes the connection between a remote shared object and the server. If a remote shared object is locally persistent, the user can make changes to the local copy of the object after this method is called. Any changes made to the local object are sent to the server the next time the user connects to the remote shared object.

connect

()method 
public function connect(myConnection:NetConnection, params:String = null):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Connects to a remote shared object on a server through a specified NetConnection object. Use this method after calling getRemote(). When a connection is successful, the sync event is dispatched.

Before attempting to work with a remote shared object, first check for any errors using a try..catch..finally statement. Then, listen for and handle the sync event before you make changes to the shared object. Any changes made locally — before the sync event is dispatched — might be lost.

Call the connect() method to connect to a remote shared object, for example:

     var myRemoteSO:SharedObject = SharedObject.getRemote("mo", myNC.uri, false);
     myRemoteSO.connect(myNC);
     

Parameters

myConnection:NetConnection — A NetConnection object that uses the Real-Time Messaging Protocol (RTMP), such as a NetConnection object used to communicate with Flash Media Server.
 
params:String (default = null) — A string defining a message to pass to the remote shared object on the server. Cannot be used with Flash Media Server.


Throws
Error — Flash Player could not connect to the specified remote shared object. Verify that the NetConnection instance is valid and connected and that the remote shared object was successfully created on the server.

See also

flush

()method 
public function flush(minDiskSpace:int = 0):String

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Immediately writes a locally persistent shared object to a local file. If you don't use this method, Flash Player writes the shared object to a file when the shared object session ends — that is, when the SWF file is closed, when the shared object is garbage-collected because it no longer has any references to it, or when you call SharedObject.clear() or SharedObject.close().

If this method returns SharedObjectFlushStatus.PENDING, Flash Player displays a dialog box asking the user to increase the amount of disk space available to objects from this domain. To allow space for the shared object to grow when it is saved in the future, which avoids return values of PENDING, pass a value for minDiskSpace. When Flash Player tries to write the file, it looks for the number of bytes passed to minDiskSpace, instead of looking for enough space to save the shared object at its current size.

For example, if you expect a shared object to grow to a maximum size of 500 bytes, even though it might start out much smaller, pass 500 for minDiskSpace. If Flash asks the user to allot disk space for the shared object, it asks for 500 bytes. After the user allots the requested amount of space, Flash won't have to ask for more space on future attempts to flush the object (as long as its size doesn't exceed 500 bytes).

After the user responds to the dialog box, this method is called again. A netStatus event is dispatched with a code property of SharedObject.Flush.Success or SharedObject.Flush.Failed.

Parameters

minDiskSpace:int (default = 0) — The minimum disk space, in bytes, that must be allotted for this object.

Returns
String — Either of the following values:
  • SharedObjectFlushStatus.PENDING: The user has permitted local information storage for objects from this domain, but the amount of space allotted is not sufficient to store the object. Flash Player prompts the user to allow more space. To allow space for the shared object to grow when it is saved, thus avoiding a SharedObjectFlushStatus.PENDING return value, pass a value for minDiskSpace.
  • SharedObjectFlushStatus.FLUSHED: The shared object has been successfully written to a file on the local disk.

Throws
Error — Flash Player cannot write the shared object to disk. This error might occur if the user has permanently disallowed local information storage for objects from this domain.

Note: Local content can always write shared objects from third-party domains (domains other than the domain in the current browser address bar) to disk, even if writing of third-party shared objects to disk is disallowed.

See also


Example  ( How to use this example )

The following code creates (and on subsequent executions, retrieves) a SharedObject object using an id with the value of hostName. A property named username is added to the data property of the SharedObject object. The flush() method is then called, followed by a check to see if the string pending, or a boolean value of true or false was returned. One should be aware that all open SharedObject instances will automatically be flushed whenever the current instance of the Flash Player is closed.
package {
    import flash.net.SharedObject;

    public class SharedObject_flush {
        private var hostName:String = "yourDomain";
        private var username:String = "yourUsername";

        public function SharedObject_flush() {
            var mySo:SharedObject = SharedObject.getLocal(hostName);
            mySo.data.username = username;
            var flushResult:Object = mySo.flush();
            trace("flushResult: " + flushResult);
            trace(mySo.data.username); // yourUsername
        }
    }
}

getLocal

()method 
public static function getLocal(name:String, localPath:String = null, secure:Boolean = false):SharedObject

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Returns a reference to a locally persistent shared object that is only available to the current client. If the shared object does not already exist, this method creates one. If any values passed to getLocal() are invalid or if the call fails, Flash Player throws an exception.

The following code shows how you assign the returned shared object reference to a variable:

var so:SharedObject = SharedObject.getLocal("savedData");

Note: If the user has chosen to never allow local storage for this domain, the object is not saved locally, even if a value for localPath is specified. The exception to this rule is local content. Local content can always write shared objects from third-party domains (domains other than the domain in the current browser address bar) to disk, even if writing of third-party shared objects to disk is disallowed.

To avoid name conflicts, Flash looks at the location of the SWF file creating the shared object. For example, if a SWF file at www.myCompany.com/apps/stockwatcher.swf creates a shared object named portfolio, that shared object does not conflict with another object named portfolio that was created by a SWF file at www.yourCompany.com/photoshoot.swf because the SWF files originate from different directories.

Although the localPath parameter is optional, you should give some thought to its use, especially if other SWF files need to access the shared object. If the data in the shared object is specific to one SWF file that will not be moved to another location, then use of the default value makes sense. If other SWF files need access to the shared object, or if the SWF file that creates the shared object will later be moved, then the value of this parameter affects how accessible the shared object will be. For example, if you create a shared object with localPath set to the default value of the full path to the SWF file, no other SWF file can access that shared object. If you later move the original SWF file to another location, not even that SWF file can access the data already stored in the shared object.

To avoid inadvertently restricting access to a shared object, use the localpath parameter. The most permissive approach is to set localPath to / (slash), which makes the shared object available to all SWF files in the domain, but increases the likelihood of name conflicts with other shared objects in the domain. A more restrictive approach is to append localPath with folder names that are in the full path to the SWF file. For example, for a portfolio shared object created by the SWF file at www.myCompany.com/apps/stockwatcher.swf, you could set the localPath parameter to /, /apps, or /apps/stockwatcher.swf. You must determine which approach provides optimal flexibility for your application.

When using this method, consider the following security model:

  • You cannot access shared objects across sandbox boundaries.
  • Users can restrict shared object access by using the Flash Player Settings dialog box or the Settings Manager. By default, an application can create shared objects of up 100 KB of data per domain. Administrators and users can also place restrictions on the ability to write to the file system.

Suppose you publish SWF file content to be played back as local files (either locally installed SWF files or EXE files), and you need to access a specific shared object from more than one local SWF file. In this situation, be aware that for local files, two different locations might be used to store shared objects. The domain that is used depends on the security permissions granted to the local file that created the shared object. Local files can have three different levels of permissions:

  1. Access to the local filesystem only.
  2. Access to the network only.
  3. Access to both the network and the local filesystem.

Local files with access to the local filesystem (level 1 or 3) store their shared objects in one location. Local files without access to the local filesystem (level 2) store their shared objects in another location.

You can prevent a SWF file from using this method by setting the allowNetworking parameter of the the object and embed tags in the HTML page that contains the SWF content.

For more information, see the following:

  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The security chapter in the Programming ActionScript 3.0 book and the latest comments on LiveDocs
  • The Flash Player Developer Center Topic: Security

Parameters

name:String — The name of the object. The name can include forward slashes (/); for example, work/addresses is a legal name. Spaces are not allowed in a shared object name, nor are the following characters:
  ~ % & \ ; : " ' , < > ? # 
  
 
localPath:String (default = null) — The full or partial path to the SWF file that created the shared object, and that determines where the shared object will be stored locally. If you do not specify this parameter, the full path is used.
 
secure:Boolean (default = false) — Determines whether access to this shared object is restricted to SWF files that are delivered over an HTTPS connection. If your SWF file is delivered over HTTPS, this parameter's value has the following effects:
  • If this parameter is set to true, Flash Player creates a new secure shared object or gets a reference to an existing secure shared object. This secure shared object can be read from or written to only by SWF files delivered over HTTPS that call SharedObject.getLocal() with the secure parameter set to true.
  • If this parameter is set to false, Flash Player creates a new shared object or gets a reference to an existing shared object that can be read from or written to by SWF files delivered over non-HTTPS connections.

If your SWF file is delivered over a non-HTTPS connection and you try to set this parameter to true, the creation of a new shared object (or the access of a previously created secure shared object) fails and null is returned. Regardless of the value of this parameter, the created shared objects count toward the total amount of disk space allowed for a domain.

The following diagram shows the use of the secure parameter:

secure shared object diagram

Returns
SharedObject — A reference to a shared object that is persistent locally and is available only to the current client. If Flash Player can't create or find the shared object (for example, if localPath was specified but no such directory exists), this method throws an exception.

Throws
Error — Flash Player cannot create the shared object for whatever reason. This error might occur is if persistent shared object creation and storage by third-party Flash content is prohibited (does not apply to local content). Users can prohibit third-party persistent shared objects on the Global Storage Settings panel of the Settings Manager, located at http://www.adobe.com/support/documentation/en/flashplayer/help/settings_manager03.html.

getRemote

()method 
public static function getRemote(name:String, remotePath:String = null, persistence:Object = false, secure:Boolean = false):SharedObject

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Returns a reference to a shared object on Flash Media Server that multiple clients can access. If the remote shared object does not already exist, this method creates one.

To create a remote shared object, call getRemote() the call connect() to connect the remote shared object to the server, as in the following:

     var nc:NetConnection = new NetConnection();
     nc.connect("rtmp://somedomain.com/applicationName");
     var myRemoteSO:SharedObject = SharedObject.getRemote("mo", nc.uri, false);
     myRemoteSO.connect(nc);
     

To confirm that the local and remote copies of the shared object are synchronized, listen for and handle the sync event. All clients that want to share this object must pass the same values for the name and remotePath parameters.

To create a shared object that is available only to the current client, use SharedObject.getLocal().

Parameters

name:String — The name of the remote shared object. The name can include forward slashes (/); for example, work/addresses is a legal name. Spaces are not allowed in a shared object name, nor are the following characters:
    ~ % & \ ; :  " ' , > ? ? #
 
remotePath:String (default = null) — The URI of the server on which the shared object will be stored. This URI must be identical to the URI of the NetConnection object passed to the connect() method.
 
persistence:Object (default = false) — Specifies whether the attributes of the shared object's data property are persistent locally, remotely, or both. This parameter can also specify where the shared object will be stored locally. Acceptable values are as follows:
  • A value of false specifies that the shared object is not persistent on the client or server.
  • A value of true specifies that the shared object is persistent only on the server.
  • A full or partial local path to the shared object indicates that the shared object is persistent on the client and the server. On the client, it is stored in the specified path; on the server, it is stored in a subdirectory within the application directory.

Note: If the user has chosen to never allow local storage for this domain, the object will not be saved locally, even if a local path is specified for persistence. For more information, see the class description.

 
secure:Boolean (default = false) — Determines whether access to this shared object is restricted to SWF files that are delivered over an HTTPS connection. For more information, see the description of the secure parameter in the getLocal method entry.

Returns
SharedObject — A reference to an object that can be shared across multiple clients.

Throws
Error — Flash Player can't create or find the shared object. This might occur if nonexistent paths were specified for the remotePath and persistence parameters.

See also

send

()method 
public function send(... arguments):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Broadcasts a message to all clients connected to a remote shared object, including the client that sent the message. To process and respond to the message, create a callback function attached to the shared object.

Parameters

... arguments — One or more arguments: A string that identifies the message, the name of one or more handler functions to attach to the shared object, and optional parameters of any type. The handler name can be only one level deep (that is, it can't be of the form parent/child) and is relative to the shared object. The arguments are serialized and sent over the connection, and the receiving handler receives them in the same order. If a parameter is a circular object (for example, a linked list that is circular), the serializer handles the references correctly.

Note: Do not use a reserved term for the function names. For example, myRemoteSO.send("close") will fail.

setDirty

()method 
public function setDirty(propertyName:String):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Indicates to the server that the value of a property in the shared object has changed. This method marks properties as dirty, which means changed.

Call the SharedObject.setProperty() to create properties for a shared object.

The SharedObject.setProperty() method implements setDirty(). In most cases, such as when the value of a property is a primitive type like String or Number, you can call setProperty() instead of calling setDirty(). However, when the value of a property is an object that contains its own properties, call setDirty() to indicate when a value within the object has changed.

Parameters

propertyName:String — The name of the property that has changed.

See also

setProperty

()method 
public function setProperty(propertyName:String, value:Object = null):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Updates the value of a property in a shared object and indicates to the server that the value of the property has changed. The setProperty() method explicitly marks properties as changed, or dirty.

For more information about remote shared objects see the Flash Media Server documentation.

Note: The SharedObject.setProperty() method implements the setDirty() method. In most cases, such as when the value of a property is a primitive type like String or Number, you would use setProperty() instead of setDirty. However, when the value of a property is an object that contains its own properties, use setDirty() to indicate when a value within the object has changed. In general, it is a good idea to call setProperty() rather than setDirty(), because setProperty() updates a property value only when that value has changed, whereas setDirty() forces synchronization on all subscribed clients.

Parameters

propertyName:String — The name of the property in the shared object.
 
value:Object (default = null) — The value of the property (an ActionScript object), or null to delete the property.

See also

Event Detail

asyncError

Event
Event Object Type: flash.events.AsyncErrorEvent
property AsyncErrorEvent.type = flash.events.AsyncErrorEvent.ASYNC_ERROR

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when an exception is thrown asynchronously — that is, from native asynchronous code.

The AsyncErrorEvent.ASYNC_ERROR constant defines the value of the type property of an asyncError event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe object dispatching the event.
errorThe error that triggered the event.

netStatus

Event  
Event Object Type: flash.events.NetStatusEvent
property NetStatusEvent.type = flash.events.NetStatusEvent.NET_STATUS

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when a SharedObject instance is reporting its status or error condition. The netStatus event contains an info property, which is an information object that contains specific information about the event, such as whether a connection attempt succeeded or whether the shared object was successfully written to the local disk.

Defines the value of the type property of a netStatus event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
infoAn object with properties that describe the object's status or error condition.
targetThe NetConnection or NetStream object reporting its status.

See also

sync

Event  
Event Object Type: flash.events.SyncEvent
property SyncEvent.type = flash.events.SyncEvent.SYNC

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Dispatched when a remote shared object has been updated by the server.

Defines the value of the type property of a sync event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
changeListAn array with properties that describe the array's status.
targetThe SharedObject instance that has been updated by the server.

See also

SharedObjectExample.as

The following code creates (and on subsequent executions, retrieves) a shared object object using the ID "application-name". When the Save button is clicked, the saveValue() method attempts to save a property named savedValue to the data property of the SharedObject object. If Flash Player must ask for permission to save the data, when the user grants or denies permission the onFlushStatus() method is called. When the Clear button is clicked, the clearValue() method deletes the value saved in savedValue; the next time the SWF file is loaded, the value that is retrieved is undefined.
package {
    import flash.display.Sprite;
    import flash.events.MouseEvent;
    import flash.events.NetStatusEvent;
    import flash.net.SharedObject;
    import flash.net.SharedObjectFlushStatus;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.text.TextFieldType;
    
    public class SharedObjectExample extends Sprite {
        
        private var mySo:SharedObject;
        
        public function SharedObjectExample() {
            buildUI();
            saveBtn.addEventListener(MouseEvent.CLICK, saveValue);
            clearBtn.addEventListener(MouseEvent.CLICK, clearValue);
            
            mySo = SharedObject.getLocal("application-name");
            output.appendText("SharedObject loaded...\n");
            output.appendText("loaded value: " + mySo.data.savedValue + "\n\n");
        }

         private function saveValue(event:MouseEvent):void {
            output.appendText("saving value...\n");
            mySo.data.savedValue = input.text;
            
            var flushStatus:String = null;
            try {
                flushStatus = mySo.flush(10000);
            } catch (error:Error) {
                output.appendText("Error...Could not write SharedObject to disk\n");
            }
            if (flushStatus != null) {
                switch (flushStatus) {
                    case SharedObjectFlushStatus.PENDING:
                        output.appendText("Requesting permission to save object...\n");
                        mySo.addEventListener(NetStatusEvent.NET_STATUS, onFlushStatus);
                        break;
                    case SharedObjectFlushStatus.FLUSHED:
                        output.appendText("Value flushed to disk.\n");
                        break;
                }
            }
            output.appendText("\n");
        }
        
        private function clearValue(event:MouseEvent):void {
            output.appendText("Cleared saved value...Reload SWF and the value should be \"undefined\".\n\n");
            delete mySo.data.savedValue;
        }
        
        private function onFlushStatus(event:NetStatusEvent):void {
            output.appendText("User closed permission dialog...\n");
            switch (event.info.code) {
                case "SharedObject.Flush.Success":
                    output.appendText("User granted permission -- value saved.\n");
                    break;
                case "SharedObject.Flush.Failed":
                    output.appendText("User denied permission -- value not saved.\n");
                    break;
            }
            output.appendText("\n");

            mySo.removeEventListener(NetStatusEvent.NET_STATUS, onFlushStatus);
        }
        
        // UI elements
        private var inputLbl:TextField;
        private var input:TextField;
        private var output:TextField;
        private var saveBtn:Sprite;
        private var clearBtn:Sprite;
    
        private function buildUI():void {
            // input label
            inputLbl = new TextField();
            addChild(inputLbl);
            inputLbl.x = 10;
            inputLbl.y = 10;
            inputLbl.text = "Value to save:";
            
            // input TextField
            input = new TextField();
            addChild(input);
            input.x = 80;
            input.y = 10;
            input.width = 100;
            input.height = 20;
            input.border = true;
            input.background = true;
            input.type = TextFieldType.INPUT;
            
            // output TextField
            output = new TextField();
            addChild(output);
            output.x = 10;
            output.y = 35;
            output.width = 250;
            output.height = 250;
            output.multiline = true;
            output.wordWrap = true;
            output.border = true;
            output.background = true;
            
            // Save button
            saveBtn = new Sprite();
            addChild(saveBtn);
            saveBtn.x = 190;
            saveBtn.y = 10;
            saveBtn.useHandCursor = true;
            saveBtn.graphics.lineStyle(1);
            saveBtn.graphics.beginFill(0xcccccc);
            saveBtn.graphics.drawRoundRect(0, 0, 30, 20, 5, 5);
            var saveLbl:TextField = new TextField();
            saveBtn.addChild(saveLbl);
            saveLbl.text = "Save";
            saveLbl.selectable = false;
            
            // Clear button
            clearBtn = new Sprite();
            addChild(clearBtn);
            clearBtn.x = 230;
            clearBtn.y = 10;
            clearBtn.useHandCursor = true;
            clearBtn.graphics.lineStyle(1);
            clearBtn.graphics.beginFill(0xcccccc);
            clearBtn.graphics.drawRoundRect(0, 0, 30, 20, 5, 5);
            var clearLbl:TextField = new TextField();
            clearBtn.addChild(clearLbl);
            clearLbl.text = "Clear";
            clearLbl.selectable = false;
        }
    }
}