Method # Session --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ## Description Session refers to two things in your web projects. The Session class in the project is a subclass of `WebSession` that you can use to add your own properties, methods and constants. Each user that connects to the web app gets their own instance of the Session class, which can be conveniently accessed using the Session method. To learn about the Session class, refer to the `WebSession` class. This topic discusses the Session method that provides you with a reference to WebSession for the active user. ## Usage ``` xojo Session.Property = Value ``` or ``` xojo Session.Method ``` | Part | Description | |----------|------------------------------------------------------------------------------------------------------------------------------------------| | Property | Any valid property of the `WebSession` class or the Session subclass in the project. | | Value | A value of the proper datatype for the Property. | | Method | Any valid method of the `WebSession` class or the Session subclass in the project. | ## Notes

Note

To refer to the current Session from within the Session object, use `Self` instead of Session as the prefix, especially in the Opening event because it may return `Nil`.

In order to see WebSession properties in the debugger, you can create a temporary variable: ``` xojo #If DebugBuild Then Var currentSession As Session = Session #EndIf ``` The reason for the pragma is that the call can be very expensive when there are lots of sessions running. This way it'll only affect performance when you're debugging. --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ### Session context Session returns `Nil` when there is no session context available. Whether a session context is present depends not on which thread the code runs on, but on the type of object whose event is firing. Events from classes with a `Web` prefix — such as `WebThread`, `WebTimer`, `WebButton`, and other web UI controls — will have a session context available when their events fire. The framework takes care of restoring the session before your code runs, even for objects like `WebTimer` whose `Location` property is set to `Server`, which runs on the main thread. Events from non-web objects — such as `Thread`, `Timer`, `Shell`, `URLConnection`, and `SerialConnection` — will not have a session context by default when their events fire, so Session will be `Nil` in those contexts. Code run directly in the `App` object is also in this category. There are less obvious cases where a session context may be present. For example, if a `WebButton` `Pressed` event (which has a session context) synchronously executes a `XojoScript`, the `XojoScript.Print` event may also have a session context as a direct result. If you need to access a Session from a context where it would otherwise be `Nil`, refer to the `Reconnecting to a WebSession` topic to learn how to restore a session context using a Session Identifier. As long as a Session is not `Nil`, it is available for use: ``` xojo If Not (Session = Nil) Then Var user As String user = Session.UserName ' your own property added to Session End If ``` --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ### Multiple browser windows If the user opens two browser windows/tabs to an app, the new window gets its own Session instance. Use cookies to determine if two sessions belong to the same user. ## Sample code This code saves the User Name and Password from a login page to properties added to the Session class: ``` xojo Session.UserName = UserNameField.Text Session.Password = PasswordField.Text ``` --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- This code gets the current Session associated with a web page: ``` xojo Var sc As WebSessionContext sc = New WebSessionContext(App.SessionForControl(Self)) ``` ## Compatibility | | | |-----------------------|-----| | **Project Types** | Web | | **Operating Systems** | All |

`WebSession`, `WebSessionContext`, `WebApplication` classes