Using a List as a condition for LINQ to SQL query

Question

I have a LINQ to SQL query that goes like this:

String NameCondition = "Test";
String EmailCondition = "test@test.com";

IQueryable<User> Users = Repository.Where(x => x.Name.Equals(NameCondition) && x.Email.Equals(EmailCondition));

But now I have a list of conditions where I would like to pull Users from if they match any of them (like an OR statement in SQL). So I have a list of dictionaries, and each dictionary is a condition with a name and email:

List<Dictionary<String, String>> Conditions;

How can I perform a LINQ to SQL query using those conditions?

Why do you have a list of dictionaries? It sounds like you're saying that each dictionary only contains one entry. Is that the case? — Daniel Pratt, Dec 22 '10 at 15:18

score 0 · Answer 1 · edited Dec 22 '10 at 15:23

0

Use PredicateBuilder by Josef Albahari

http://www.albahari.com/nutshell/predicatebuilder.aspx

Here is a sample usage.

IQueryable<Product> SearchProducts (params string[] keywords)
{
  var predicate = PredicateBuilder.False<Product>();

  foreach (string keyword in keywords)
  {
    string temp = keyword;
    predicate = predicate.Or (p => p.Description.Contains (temp));
  }
  return dataContext.Products.Where (predicate);
}

edited Dec 22 '10 at 15:23

abatishchev

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answered Dec 22 '10 at 15:17

Jahan Zinedine

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why the edit Daniel.?? i thought the usage example supported the link well – jim tollan Dec 22 '10 at 15:22
@jim It's joyful to use the privileges :-) – Jahan Zinedine Dec 22 '10 at 15:24
ab(use) in my case probably :-) – jim tollan Dec 22 '10 at 15:27
Something strange is going on. I don't remember if the example was in the version I edited, however I definitely did not remove it. I only altered the formatting of the link. It was originally backtick-quoted, which caused the link not to work. – Daniel Pratt Dec 22 '10 at 16:05
I think this is a result of the '5-minute window' feature of SO: http://meta.stackexchange.com/questions/9090/is-there-an-editing-grace-period-on-answers-after-they-have-been-posted – Daniel Pratt Dec 22 '10 at 16:16

score 0 · Answer 2 · edited May 23 '17 at 09:58

0

Instead of dictionary use List<KeyValuePair<string, string>> in .NET 3.5 and List<Tuple<string, string>> in .NET 4.0.

See some kind similar question

edited May 23 '17 at 09:58

Community

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1

answered Dec 22 '10 at 15:27

abatishchev

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Using a List as a condition for LINQ to SQL query

2 Answers2

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