[Code Update] SDK and Microsoft Press Both Wrong?? Custom Fields in the schema.xml

UPDATE

For those who missed my original article (SDK and Microsoft Press Both Wrong?? Custom Fields in the schema.xml) , you can find it here!

 

I finally got round to posting the code that goes with this article ..

 

Please find below the details on code for an SPFeatureReceiver class, that will automatically push down changes from your Content Type Features

(you will need to attach the code to your feature using the ReceiverAssembly and ReceiverClass attributes in your feature.

 

The code needs to be created as a Class in a Class Library, with Microsoft.SharePoint.dll added as a reference, and then added as a Using statement in the class itself.

 

Code Sample

 

EDIT - Thanks to a quick spot from Nick's SharePoint blog, I have updated the code to match! Thanks Nick!

 

class

ContentTypeInstaller : SPFeatureReceiver

{

// CODE DESCRIPTION

// ----------------

/*

* This is a feature handler which should be paired

* with a content type feature.

*

* We have identified a problem with Content Types,

* where the content type site columns are not pushed

* down to custom list definitions, until they are

* "modified" first.

*

* This feature will interrogate all of the associated

* xml files that are attached to the feature.

* Once found, it will "modify" each of the custom fields

* that are referenced.

*

* This should allow list definitions to use the content

* type columns, without declaring them in the schema.xml

*/

public override void FeatureActivated(SPFeatureReceiverProperties properties)

{

using(SPSite site = (SPSite)properties.Feature.Parent)

{

SPWeb web = site.OpenWeb(

"");

// loop through each of the elements in the feature

foreach (SPElementDefinition element in properties.Definition.GetElementDefinitions(CultureInfo.CurrentCulture))

{

#region

Loop through feature elements

 

// retrieve the xml content for the feature element

XmlNode content = element.XmlDefinition;

// only continue if the element is a content type definition

if (content.Name == "ContentType")

{

// grab a new Content Type object

string strCTypeID = content.Attributes["ID"].Value;

SPContentType cType = web.ContentTypes[

new SPContentTypeId(strCTypeID)];

#region

Get FieldRef Order from Content type

// grab the original order, we will need this later

string[] fieldOrder = new string[cType.FieldLinks.Count];

int x = 0;

foreach (SPFieldLink fieldlink in cType.FieldLinks)

{

fieldOrder[x] = fieldlink.Name;

x++;

}

#endregion

#region

Add new columns to the content type

// loop through each sub-node in the Content Type file

foreach (XmlNode node in content.ChildNodes)

{

#region

loop through sub nodes

// only continue for

// the FieldRefs collection

if (node.Name == "FieldRefs")

{

foreach (XmlNode fieldRef in node.ChildNodes)

{

#region

Loop through FieldRefs

// only apply for FieldRef tags

if (fieldRef.Name == "FieldRef")

{

// get the FieldID and use it to

// retrieve the SPField object

string fieldID = fieldRef.Attributes["ID"].Value;

//SPFieldLink fieldLink = cType.FieldLinks[new Guid(fieldID)];

SPField field = cType.Fields[

new Guid(fieldID)];

// first we need to remove the fieldref

cType.FieldLinks.Delete(

new Guid(fieldID));

// and save, pushing this change down

cType.Update(

true);

// NOTE - this will NOT delete any content

// in existing lists!

// now add the field back in again

cType.FieldLinks.Add(

new SPFieldLink(field));

// and call an update, pushing down all changes

cType.Update(

true);

// NOTE - this is what adds the column to those

// lists who don't already have it.

}

#endregion

}

 

}

#endregion

}

#endregion

#region

Apply changes

// reset the field order

// it is possible that adding and

// removing fields would have

// affected this

cType.FieldLinks.Reorder(fieldOrder);

// force update of the content type,

// pushing down to children

cType.Update(

true);

#endregion

}

#endregion

}

}

}

public override void FeatureDeactivating(SPFeatureReceiverProperties properties)

{

}

public override void FeatureInstalled(SPFeatureReceiverProperties properties)

{

}

public override void FeatureUninstalling(SPFeatureReceiverProperties properties)

{

}

}

Enjoy, and happy coding!