SearchManager vs ContentSearchManager?

Question

I've nerver really delved into the search capabilites of sitecore, up until now I've always used what the previous developer used. I was looking at an issue where certain predicates didn't seem to be woking in the below piece of code:

public IEnumerable<IndexedEvent> SearchItems(Expression<Func<IndexedEvent, bool>> predicate)
{
   using (IProviderSearchContext _context = ContentSearchManager.GetIndex(indexName).CreateSearchContext())
   {
       IEnumerable<IndexedEvent> results = _context
                .GetQueryable<IndexedEvent>()
                .Where(predicate);

            return results;

   }
}

I didn't write the above, I'm just using it.

I was looking into my issue when I came across this example question Very basic usage of sitecore search which included the code:

// use id of from the index configuration
using (IndexSearchContext indexSearchContext = SearchManager.GetIndex("my-custom-index").CreateSearchContext())
{
    // MatchAllDocsQuery will return everything. Use proper query from the link below
    SearchHits hits = indexSearchContext.Search(new MatchAllDocsQuery(), int.MaxValue);
    // Get Sitecore items from the results of the query
    List<Item> items = hits.FetchResults(0, int.MaxValue).Select(result => result.GetObject<Item>()).Where(item => item != null).ToList();
}

Now this seems to use a totally different method to query the index, IndexSearchContext where as my code (not written by me) uses IProviderSearchContext. I can't find any documentation on either and they reside in totally different assemblies.

So it begs the question, when should I use IndexSearchContext and when should I use IProviderSearchContext? Is there any fundermental difference here or is it just two ways of achiving the same nett result?

Answer 1

The question and code you are referring to with the SearchManager and IndexSearchContext is from Sitecore 6. The code with the ContentSearchManager and IProviderSearchContext is for Sitecore 7 or 8 (well, 7+ that is).

So, if your code is for Sitecore8 as your tag and code example suggests, the ContentSearchManager is the way to go.