HierarchyID in Entity Framework not working

Mohanavel picture Mohanavel · Nov 30, 2010 · Viewed 10.2k times · Source

We are using WCF Data Service based on an Entity Framework model for our application.

In this we need to add the table with a column of type HierarchyId. When I add that table to the EDMX file, the HierarchId column is not appearing in the class file.

What should I do to make use of HierarchyID? I read that Entity Framework is not supporting HierarchyID, so how can I achieve this?

Answer

marc_s picture marc_s · Nov 30, 2010

You can always convert a HierarchyId to its string representation - something like /1/3/4/1 - and send that string across the WCF data service.

Update: if you add this computed, persisted column to your SQL Server table, that new column should definitely show up in your EF model and you should be able to use this to send it back over WCF and WCF Data Services:

ALTER TABLE dbo.YourTable
ADD HierarchyString AS (your hierarchyID field).ToString() PERSISTED

Update #2: read the docs! You can parse back a string like /1/3/4/1 into a HierarchyId type - either use the HierarchyId::Parse(string) or the usual CAST(string as HierarchyId) methods to do so.