Using Contains to do an IN statement within and LINQ clause using the Entity Framework

Question

I'm trying to dynamically build a LINQ where statement but I'm having problems trying to write a IN statement using the contains method on a list.

Here is my code:

IQueryable<Customer> customers =
                (from cus in objectCustomer
                 select cus); \\objectCustomer is all customers

//List of customer ID's passed into the method.
string[] sCustomerIDs = (string[])DictionaryParameters["CustomerIDs"];
customers = customers.Where(c => c.Assets.Any(a => sAssetIDs.Contains(a.UN_Asset.ToString())));

return customers.Cast<T>().ToList();

When the return line is run I receive the following error: LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression.

Any ideas? If I change IQueryable to IEnumerable to query runs but I need to use IQueryable as I'm using the Entity Framework and IEnumerable returns all the records before my filter takes place.

Many Thanks.

score 2 · Answer 1 · answered Jan 05 '12 at 09:50

please try this:

string[] sCustomerIDs = (string[])DictionaryParameters["CustomerIDs"];    

IQueryable<Customer> customers =   
            (from cus in objectCustomer  
             where sCustomerIDs.Contains(cus.*[Your Field]*)
             select cus);

Using Contains to do an IN statement within and LINQ clause using the Entity Framework

1 Answers1