Sitecore Search: how to query by Id using the indexer on the SearchResultItem

Question

I'm trying to do this:

queryable.Where(i => i["_template"] == templateId);

Where templateId is a Guid string, but it doesn't work. However, this does work:

queryable.Where(i => i["_templatename"] == templatename);

What do I need to do in order to filter by ID?

P.S. I realise I can use the typed template ID property, but I need the field name to be dynamic.

Answer 1

This probably isn't working because the value stored inside i["_template"] is the parsed GUID value from the index.

Try using:

Sitecore.ContentSearch.Utilities.IdHelper.NormalizeGuid(templateId)

This will convert any GUID to the format which is stored inside the search index.

Answer 2

Can't you do something mode along the lines of:

var predicate = PredicateBuilder.True<T>();

predicate = predicate.Where(i => i.TemplateId = templateId);

var results = queryable.Where(predicate);

There is more info on this here: https://doc.sitecore.net/sitecore%20experience%20platform/developing/developing%20with%20sitecore/search%20and%20item%20buckets/linq%20to%20sitecore