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I’m doing tests with Entity Framework and I had a problem when placing a array as a parameter.
Why when I assign the conversion of array in a function variable and directly in the method parameter does not work?
This behavior is normal?
If yes, what name?
List<Product> product = new List<Product>()
var p = product.ToArray();
db.Product.AddOrUpdate(x => x.Id, p);
List<Product> product = new List<Product>()
db.Product.AddOrUpdate(x => x.Id, product.ToArray());
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This is because LINQ to Entities requires the entire LINQ expression to be translated into a server query and therefore you cannot call a method from outside, in your case Linq does not reorganize the data within its methods, that is to say there is no way to convert your product to array product.ToArray() within the method AddOrUpdate this method expects an array and not an object calling the method ToArray() and return an array.
For this to work, you will need to restructure your query expression into an expression that Entity Framework can handle.
As you can see in DbSetMigrationsExtensions.AddOrUpdate, the third parameter of this method is params TEntity[] entities, for not being a Expression does not undergo any kind of SQL translation by EF.
the Addorupdate method expects an array and not an object that calls the Toarray() method and returns an array. Ef does not know how to do this.
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Doesn’t work like? It’s certainly not because of missing one
)indb.Product.AddOrUpdate(x => x.Id, product.ToArray();or is?– ramaral
This is not why. When it is converted into the parameter it just does not insert, it does not give any error.
– Jean Gustavo Prates
You have how to explain how this variable
productis formed?– Leonel Sanches da Silva
@I edited the question.
– Jean Gustavo Prates
But you don’t need to convert to array to use
AddOrUpdate. And the list is empty. This is correct?– Leonel Sanches da Silva
@Ciganomorrisonmendez the list comes through a Post, put only to identify that is a list of objects. Addorupdate expects a Product type array (params Product[]).
– Jean Gustavo Prates