Handling object events

Objects include all data structures used within Xperience, such as user accounts, media libraries, search indexes, or setting keys. By handling the events that occur during the life cycle of objects, you can add custom functionality to almost any part of the system. In the API, objects are represented by Info classes.

Use the following classes to access the object events:

• ObjectEvents – events triggered for all object types
• <name>Info.TYPEINFO.Events – events triggered only for a specific object type, for example: UserInfo.TYPEINFO.Events

See the Global event reference for information about the available events.

Example

The following example demonstrates how to use event handlers to customize the behavior of a specific type of object.

The sample code extends the functionality of media libraries by creating a handler for the Insert.After event of the MediaLibraryInfo class. This event occurs whenever a media library is created. The custom logic automatically adds a default sub-folder for every new media library.

1. Open your Xperience solution in Visual Studio.
2. Create a custom module class.
   • Add the class into a custom assembly (Class Library project) within the solution.
3. Override the module’s OnInit method and assign a handler method to the MediaLibraryInfo.TYPEINFO.Events.Insert.After event.

using CMS;
using CMS.DataEngine;
using CMS.MediaLibrary;
using CMS.SiteProvider;

// Registers the custom module into the system
[assembly: RegisterModule(typeof(CustomMediaModule))]

public class CustomMediaModule : Module
{
    // Module class constructor, the system registers the module under the name "CustomMedia"
    public CustomMediaModule()
        : base("CustomMedia")
    {
    }

    // Contains initialization code that is executed when the application starts
    protected override void OnInit()
    {
        base.OnInit();

        // Assigns a handler to the Insert.After event for the MediaLibraryInfo class
        // This event occurs after the creation of every new media library
        MediaLibraryInfo.TYPEINFO.Events.Insert.After += MediaLibrary_InsertAfterEventHandler;        
    }

    /// <summary>
    /// Automatically creates a child folder for new media libraries
    /// </summary>
    private void MediaLibrary_InsertAfterEventHandler(object sender, ObjectEventArgs e)
    {
        // Checks that the media library was successfully created
        if (e.Object != null)
        {
            // Gets an info object representing the new media library
            MediaLibraryInfo mediaLibrary = (MediaLibraryInfo)e.Object;

            // Gets the media library's site
            SiteInfo site = SiteInfo.Provider.Get(mediaLibrary.LibrarySiteID);

            // Creates a "Default" sub-folder in the media library
            MediaLibraryInfoProvider.CreateMediaLibraryFolder(site.SiteName, mediaLibrary.LibraryID, "Default");
        }
    }
}

To try out the functionality of the custom event handler, create a new media library on any website:

1. Open the Media libraries application in the Xperience administration interface.
2. Click New media library.
3. Enter a Display name and Folder name for the new media library.
4. Click Save.

The system adds the media library and automatically creates a Default sub-folder.