The requirement

Recently a simple requirement came up: “Redirect the user to the view-form of an item after he creates a new item”. Sounds simple, right? …

The default behavior of SharePoint is to redirect the user to the url defined by the Source-parameter. If this parameter is not given the default view (mostly AllItems.aspx) will be used.

The result

The implementation of the requirement can be seen in this short screencast. After the user creates a new item he will be redirected to review the item-properties.

The way it should be

Not amazed by the pictures you just saw? One would think its easy to achieve this behavior. Simply add an EventReceiver to the desired list and listen to the ItemAdded-event and redirect the user…
In theory this is should work. The problem is that there is no HttpContext.Current available inside the ItemAdded-method.

The HttpContext

The only way to get the current HttpContext is within the constructor of your custom EventReceiver during a asynchronous event synchronous event (ItemAdding, ItemUpdating) as shown in the following pseudo code.

public class CustomEventReceiver : SPItemEventReceiver
{
    private HttpContext _currentContext = null;
 
    public CustomEventReceiver () : base ()
    {
        if (null != HttpContext.Current)
        {
            _currentContext = HttpContext.Current
        }
    }
 
    public override void ItemAdding (SPItemEventProperties properties)
    {
       // Here one can use _currentContext and redirect ...
    }
}

But now another problem arises. If you redirect the current thread is aborted and the item is never added to the list/library

// Will abort the thread
_currentContext.Redirect("http://somewhere/to/go");
 
// Will NOT abort the thread but the redirection is ignored
_currentContext.Redirect("http://somewhere/to/go", false);
 
// What a mess!

The magic

The only possible solution is to “manually” add the item so the redirection works as shown in the next code-block. The manual addition of the new item is necessary because the properties.ListItemId within ItemAdding is 0. But we need this ID to build the destination url in the form e.g. http://hostname/web/listname/DispForm.aspx?ID=22

public class CustomEventReceiver : SPItemEventReceiver
{
    // Code omitted ... see above
 
    public override void ItemAdding (SPItemEventProperties properties)
    {
        // Get a "reference" to the list
        SPSite siteColl = new SPSite (properties.SiteId);
        SPWeb site = siteColl.OpenWeb (properties.RelativeWebUrl)
        SPList list = site.Lists[properties.ListId];
 
        // Add the item and fill it with the values from properties
        DisableEventFiring ();
        SPListItem itemToAdd = list.Items.Add ();
        // ... 
        EnableEventFiring ();
 
        // Cleanup
        site.Dispose ();
        siteColl.Dispose ();
 
        // Redirect
        SPUtility.Redirect (targetUrlOfNewItem,
            SPRedirectFlags.Default, _currentContext);
    }
}

Hint: Because the form used to display an item can change you should retrieve it via the SPList.Forms[PAGETYPE.PAGE_DISPLAYFORM]-property.

Conclusion

The HttpContext.Current is only available within the constructor of your event receiver when handling synchronous events like ItemAdding, ItemUpdating.

I just created a simple tool that allows the easy installation (and deletion) of EventReceiver-Definitions with SharePoint. It’s a stand-alone tool written in C# and it must be executed on the Server that runs SharePoint.

The tool is named “EventReceiver-Installer” and is now in Version 1.0 1.1.

Features

• Browse web-applications
• Categorized view of EventReceivers
• Deletion of EventReceiver-Definitions
• Adding of multiple EventReceiver-Definitions with one click
• Retrieves the assemblies full-name (no more Reflector required)

Screenshots

Main view

Info view

Add new EventReceier

Add new EventReceiver 2

Delete EventReceiver-Definition

Delete EventReceiver-Definition 2

Download

Your can download it here (443KB) for free. The license is included in the archive.

Future

This is Version 1.1 and there will be additional improvements.

• Support of Document-Libraries and Websites
• Support for different credentials (not the current user)
• Multi-Deletion of EventReceiver-Definitions
• Definition types grouped be target (list, document library, website)