Question

I have the following query that performs a “AND” on-demand:

var products = // Selecting a list of products in anywhere based in a filter...

foreach (var product in products)
{
    query = query.Where(p => p.Code == product.Code); // with this way, this query make no sense because this happens in any scenario, never a code can be more than one code.
}

So, how can i do the same query but performing a “OR” on-demand (so that the query makes sense)?

Answer 1

You can use the facsimile of an IN for LINQ:

var productCodeList = products.Select(p => p.Code).ToList();

query = query.Where(p => productCodeList.Contains(p.Code));

It’s basically saying:

SELECT   *
FROM     products
WHERE    code IN (<list_of_codes>)