How to use parameter array navigation properties EF linq ?

Rupesh Kahane

9y1.2kLINQ

I have a table structure with relationship in between three tables.

I have added edmx file into my project as below.

I would like to use parameter array navigation properties entity framework using linq.

I have written some code in controller like

parames1 = v => v.LoginInfo;
parames2 = v => v.LoginInfo.UserDetail;
[] paramesArray = new Expression>[] { parames1, parames2 };
var userPost = UnitoffWork.UserPostRepository.GetAll(navigationProperties: paramesArray).Select(u => new HomeViewModel(u));

I am not able to implement this.

getting some errors like

1. parames1 does not exist.

2. can not create an instance of abstarct class or interface 'System.Linq.Expressions.Expression'

Please suggest how can i get all data in single variable from mutliple tables.

Thanks

3 Replies

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Chetan Ranpariya9y ago
Accepted answer
Hi Rupesh,

I found the solutiion.

You need to create your expressions as following.
Expression> parames1 = v => v.LoginInfo;

Expression>> parames2 = v => v.LoginInfo.UserDetails; //Here I am assuming that LoginInfo.UserDetails if of type List. You can change here if it is different than my assumption.

Expression[] paramesArray = new Expression[] { parames1, parames2 };
I hope this will solve your problem.
Thanks and regards,
Chetan Ranpariya
Bikesh Srivastava9y ago
I think its not big deal.
just create object of context and get according table,
have tried please tell me.
Chetan Ranpariya9y ago
Hi Rupesh

Can you share the method details of UnitoffWork.UserPostRepository.GetAll ?

It is sure that you can not create object of System.Linq.Expressions.Expression as it is an astract class.

Also can you tell on which lines you are getting errors?

Thanks and regards,
Chetan Ranpariya