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Linq. Select.

Hello,

I have two tables:
Polls PollID, Question
Options OptionID, Answer

Given a OptionID I want to get the poll to which the Option "Belongs":
Poll poll = database.Polls.Select(p =p.Options.Select(o =>
o.OptionID = id)).SingleOrDefault;

I am not sure if this is the right way but I am getting an error
anyway:
Cannot convert method group 'SingleOrDefault' to non-delegate type
'MyApp.Models.Poll'. Did you intend to invoke the method?

I have all relations between tables well defined and I used LinqToSQL
classes.

How should I do this?

Thanks,
Miguel
Nov 13 '08 #1
1 3017
shapper wrote:
I have two tables:
Polls PollID, Question
Options OptionID, Answer

Given a OptionID I want to get the poll to which the Option "Belongs":
Poll poll = database.Polls.Select(p =p.Options.Select(o =>
o.OptionID = id)).SingleOrDefault;

I am not sure if this is the right way but I am getting an error
anyway:
Cannot convert method group 'SingleOrDefault' to non-delegate type
'MyApp.Models.Poll'. Did you intend to invoke the method?

I have all relations between tables well defined and I used LinqToSQL
classes.

How should I do this?
First of all, SingleOrDefault is a method and methods are called this way:

Poll poll = database.Polls.Select(p =p.Options.Select(o =>
o.OptionID = id)).SingleOrDefault();

However I don't think you want a Select, you want a Where e.g.

Poll poll = database.Polls.Where(p =p.Options.Any(o =>
o.OptionID = id)).SingleOrDefault();
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/
Nov 13 '08 #2

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