I need the most efficient way to get the value of the searchName, or if null return searchName. I am returning just a single string, so maybe I should search itemRepository.Item instead of Items
return itemRepository.Items()
.Where(i => i.Name.Contains(searchName))
.Select(i => i.Value)
.FirstOrDefault() ?? searchName;
As long as Items() returns an IQueryable<Item> directly from the database, then this code is just about as fast as you can get it. If not, I think your Items() method will be the main bottleneck in this code.
From your comment it sounds like Items() is indeed trying to do more work than necessary. You should either directly reference the IQueryable collection of the repository and bypass the Items() method or focus your efforts on improving the efficiency of that method.
Itemsa method rather than a property (as evidenced by the())? Other than that question, this seems exactly the canonical way I'd do what you're looking for. \$\endgroup\$Valueof those that containsearchNamein itsName. \$\endgroup\$.Select()and the.FirstOrDefault(), but other than that, there's nothing else you can do to this query. \$\endgroup\$