CODEWITHSUNDEEP
sqllinqlinq-to-entities
ShaneKm
ShaneKm

Reputation: 21308

LINQ case sensitive

How to make LINQ case sensitive and NOT case sensitive depending on the situation?

I'm using sql server 2008 and Entity Framework 4.0.

I changed the COLLATION to make SQL Server case sensitive. so that for scenarios like these:

 query = query.Where(x => x.Username == username);

it works great. However I need to be able to pull out data from db ignoring case when searching by subject (or name or similar) like so:

query = query.Where(x => (x.Name.Contains(Name)));

which doesn't work when record is "TestString" and i'm looking for "test" or "Test" or similar. How would i make it so that when it would find a text or part of a string in a text? thanks

Upvotes: 13

Views: 22265

Answers (4)

Ivan Farkas
Ivan Farkas

Reputation: 361

query = query.Where(x => string.Equals(x.Name, Name, StringComparison.CurrentCultureIgnoreCase));

Upvotes: 8

Femaref
Femaref

Reputation: 61427

Queryable.Contains has an overload taking an IEqualityComparer<T> used for comparision. See msdn. If you supply a case insensitive comparer, this should work - I'm quite sure there is one in the framework already.

Upvotes: 2

xanatos
xanatos

Reputation: 111810

Read my reply to this:

String.Equals() not working as intended

It isn't the reply you wanted, probably :-)

Ah... and if you have to convert to the same case to make comparisons, ToUpper is better than ToLower. Don't ask me why. But you can read here: Case insensitive string compare in LINQ-to-SQL

Upvotes: 2

user
user

Reputation: 6947

LINQ has no concept of case sensitivity, it only cares about boolean evaluation. So if you want to ignore case, you should do something like:

query = query.Where(x => (x.Name.ToLower().Contains(Name.ToLower())));

Chances are you will want to pass a CultureInfo to ToLower() (or use ToLowerInvariant()), and you might want to cache the result of Name.ToLower() so as to not have to perform that operation a potentially large number of times, but this should get you started.

Upvotes: 21

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