EF Query using .Contains() and .ToLowerInvariant() Results in no matches when match is found at the end of a string

Question

Is it possible to step into a linq query? I have a linq to entity framework 4 query in it's simplest form:

List = List.Where(f => f.Value.ToString().ToLowerInvariant().Contains(filter.ToLowerInvariant()));

It's a query against an Entity Framework DbContext and I'm having trouble seeing why it works for something like:

List searching for 001 yields no results against the following list

Test001
Test002
Test003
Test004

However any other search yields results (Such as t00 or Test)

Update

Basically I'm looking for why a query such as the above wouldn't return a result when I'm using a contains and the value matches the end of a string vs just the middle or begining. It's really confusing.

OK, it appears to have something to do with ToLowerInvariant() - when I removed that method it works just fine.

possible duplicate of [How do I view the SQL generated by the entity framework ?](http://stackoverflow.com/questions/1412863/how-do-i-view-the-sql-generated-by-the-entity-framework) — Robert Harvey, Dec 27 '10 at 21:32
Sorry everybody but I've modified my question slightly based on the responses so a lot of these are no longer valid... — MyNameIsJob, Dec 27 '10 at 22:02

score 31 · Accepted Answer · answered Jan 04 '11 at 15:51

31

It appears that ToLowerInvariant() produces the error. ToLower() works just fine.

answered Jan 04 '11 at 15:51

MyNameIsJob

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score 2 · Answer 2 · answered Dec 27 '10 at 21:29

2

try working with linqpad

answered Dec 27 '10 at 21:29

Dani

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How does linqpad work with EF4 POCO objects? I only see linq-to-sql. – MyNameIsJob Dec 27 '10 at 21:56
1

This is a generic solution. – Fabio Milheiro May 04 '16 at 12:50

score 0 · Answer 3 · answered Dec 27 '10 at 21:46

As Dani suggested, LinqPad is a great tool for this. And, even though it will not allow you to "step into" Linq queries, you can use an extended method offered in LinqPad named Dump() that will show you the value of IEnumerable or IQueryable objects as you progress through your query. It is extremely useful.

score 0 · Answer 4 · answered Dec 27 '10 at 21:50

Is this query being run against the database (LINQ to EF) or against objects already in memory (LINQ to objects). I'm guessing that it is LINQ to objects based on a comment you made on another answer, in which case you should be able to set a breakpoint in the lambda expression.

score -1 · Answer 5 · answered Dec 27 '10 at 22:04

-1

Why don't you do a selection on that ToLowerInvariant() to see what it is returning.

answered Dec 27 '10 at 22:04

tster

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EF Query using .Contains() and .ToLowerInvariant() Results in no matches when match is found at the end of a string

Update

5 Answers5