CODEWITHSUNDEEP
c#linq
James
James

Reputation: 1945

Getting error while trying to use contains in Linq

I get array of strings from my client. Then in my webapi i split it as following

var splitId = string.Join(",", ids);

Then i my Linq query i use above variable

This is my Linq query

var query = tableARepository.AsQueryable()

.Where(a=> splitId.Contains(a.Id.ToString()))
.Select(a => new {
    Id = a.Id
,   Name = a.Name
,   FkId = tableBRepository.AsQueryable().Min(b => b.fkid=a.id)
});

I get this exception:

LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression.","

This is because of Contains. How can i fix this error?

Upvotes: 1

Views: 2678

Answers (1)

Habib
Habib

Reputation: 223412

Instead of converting your ids to concatenated string, keep them in a List<T>/IEnumerable<T> and then query against that like:

Based on your comment:

Ids are defined as string[] ids

You should convert them to IEnumerable<int> or List<int> like:

List<int> integerIds = ids.Select(int.Parse).ToList();

and then in your query:

var query = tableARepository.AsQueryable()
.Where(a=> integerIds.Contains(a.Id))

Just make sure that ids contains elements of same type as your table Id

The reason you are getting the exception is due to the call to ToString in your LINQ query, the provider is trying to convert it under laying data source language (May be SQL) but it can't.

Upvotes: 5

Related Questions