Question

This used to work for me and then it failed. I want to return only those items that contain all the filters, not at least one filter as it is doing now. WHat is wrong here?

private IQueryable<IndexItem> FilteredIndex (IQueryable<IndexItem> index, IEnumerable<string> filters)      {          var filteredIndex= from f in filters.AsQueryable()                 where f.Length>0                from i in index                 where i.FilterNames.Contains(f)                select i;         return filteredIndex;    } 

Answer 1

How about something like:

foreach(string s in filters) {     if(s.Length == 0) continue;     string tmp = s; // because of 'capture' problem     index = index.Where(i => i.FilterNames.Contains(tmp)); } return index; 

This applies a succession of Where clauses, covering all the filters – essentially AND.