Problem with LINQ to Entities and String.StartsWith

.net linq entity-framework linq-to-entities
ProfK picture ProfK · Jun 13, 2009 · Viewed 24k times · Source

I'm trying to build a search page using LINQ to Entities, but the following code is giving me a runtime error about l.t.e. not recognising 'Boolean StartsWith(). The code compiles just fine. How can I work around this better than shipping the StartsWith filtering out to a stored proc?

    return from dp in dents.DirectoryPersonEntrySet
           where
               ((dp.LastName.StartsWith(searchTerm, StringComparison.CurrentCultureIgnoreCase)) ||
                (dp.Department.StartsWith(searchTerm, StringComparison.CurrentCultureIgnoreCase)) ||
                dp.Extension.StartsWith(searchTerm, StringComparison.CurrentCultureIgnoreCase))
           select dp;

Answer

BengtBe picture BengtBe · Jun 13, 2009

I would guess that EF doesn't support the overload of StartsWith that takes a StringComparison parameter.

It should support StartsWith, EndsWith and Contains, so maybe you can try:

dp.LastName.StartsWith(searchTerm)

or:

dp.LastName.ToLower().StartsWith(searchTerm)

and then make sure that searchTerm is also lowercase.

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