SPItemEventReceiver Class

Provides methods for trapping events that occur to items. This class is never instantiated.


Namespace:  Microsoft.SharePoint
Assembly:  Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Available in Sandboxed Solutions: Yes
Available in SharePoint Online

public class SPItemEventReceiver : SPEventReceiverBase

This class is not instantiated but the item event receiver class of a custom event handler must derive from this class and override its methods for the event types that are handled.

If an item is moved, it is treated in the same way as an item that has been removed and then added.

Before and After properties are guaranteed for post events on documents, but Before properties are not available for post events on list items.

The following code example uses this class to add an item to a specified Announcements list whenever an attachment is added to a list.

using System;
using Microsoft.SharePoint;

namespace Example_Namespace
    public class Class_Name : SPItemEventReceiver
        public override void ItemAttachmentAdded(SPItemEventProperties properties)
            using(SPSite oSiteCollectionEvent = new SPSite(properties.SiteId))
                SPWeb oSiteEvent = oSiteCollectionEvent.OpenWeb(properties.RelativeWebUrl);
                SPListItemCollection oItemsEvent = oSiteEvent.Lists[properties.ListTitle].Items;
            using(SPSite oSiteCollection = new SPSite("http://Top_Site"))
                SPWeb oWebsite = oSiteCollection.OpenWeb("Website_Name");
                SPList oList = oWebsite.Lists["Announcements"];
                SPListItemCollection collListItems = oList.Items;

                SPListItem oItem = collListItems.Add();
                oItem["Title"] = properties.UserDisplayName + " added an attachment to " + oItemsEvent[properties.ListItemId].Title + " in list " + properties.ListTitle + " at " + properties.WebUrl;

Certain objects implement the IDisposable interface, and you must avoid retaining these objects in memory after they are no longer needed. For information about good coding practices, see Disposing Objects.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.