Override the custom field rendering in a list view

Question

When creating a custom field in SharePoint 2010, what method do I need to override to control what is rendered for the custom field type in the list where it is used?

I tried overriding GetFieldValue to no effect.

Answer 1

@Marek is right in his assertion that you should use XSLT. However, in 2010 (only) there are functions you can override to alter a field's output:

• GetFieldValueAsText is used by most field types for rendering
• GetFieldValueAsHTML is used by Note fields and similar

Each of these accepts an Object value input, which is either the raw data directly from the list, or the output from the <RenderPattern Name="DisplayPattern"> in the fldTypes...xml (if you're using <Field Name="CAMLRendering">TRUE</Field>).

The output from whichever of these functions is used is then pushed through the XSLT (if you've provided any) and rendered.

I haven't seen any examples of this method being used in the wild, however (we don't use it due to 2007 incompatibility) so I'd advise caution.

Answer 2

SharePoint 2010 renders fields on a list view is with XSLT style sheets, so there is no method to override. If you want a your own way of rendering on list views, you need to create a custom XSLT style sheet named fldtypes_*.xsl and deployed it to (14 hive)\TEMPLATE\LAYOUTS\XSL.

• How to: Create a Custom Field Type (paragraph 3. (Optional) Create a Custom XSLT Style Sheet)
• How to: Customize the Rendering of a Field on a List View

Answer 3

A field type's rendering can be controller by binding it to a BaseFieldControl derived custom control:

http://www.chakkaradeep.com/post/SharePoint-Creating-a-custom-field.aspx