我怎样才能从 sql 风格以流畅的风格重写这个 LINQ 查询？

Question

我需要以流畅的 LINQ 风格编写此 LINQ 查询（“where result =”）。

public async Task<List<Product>> ListProductsInOrderByOrderId(int orderId)
{
    var productsList = await _context.OrderProducts.Where(or => or.OrderId == orderId).ToListAsync();

    var result =  from prod in _context.Products
        join meta in _context.OrderProducts on prod.Id equals meta.ProductId 
        select new Product
                        {
                            Id = prod.Id,
                            Name = prod.Name,
                            Genre = prod.Genre,
                            RatingByAge = prod.RatingByAge,
                            DateCreated = prod.DateCreated,
                            Price = prod.Price,
                            Count = prod.Count,
                            TotalRating = prod.TotalRating

                        };

    var collectionOfProducts = await result.ToListAsync();

    return collectionOfProducts;
}

你能帮帮我吗？

Answer 1

这应该有效：

var result = _context.Products.
  Join(_context.OrderProducts, prod => prod.prodId, meta => meta.ProductId, (prod,meta) => new { prod, meta }).
  Select(x => new Product
  {
     Id = x.prod.Id,
     Name = x.prod.Name,
     Genre = x.prod.Genre,
     RatingByAge = x.prod.RatingByAge,
     DateCreated = x.prod.DateCreated,
     Price = x.prod.Price,
     Count = x.prod.Count,
     TotalRating = x.prod.TotalRating
  });

Answer 2

products.SelectMany(prod => orderProducts.Where(meta => Equals(prod.Id, meta.ProductId))
        .Select(meta => new Product
                        {
                            Id = prod.Id,
                            Name = prod.Name,
                            Genre = prod.Genre,
                            RatingByAge = prod.RatingByAge,
                            DateCreated = prod.DateCreated,
                            Price = prod.Price,
                            Count = prod.Count,
                            TotalRating = prod.TotalRating
                        }))).ToList();

我怎样才能从 sql 风格以流畅的风格重写这个 LINQ 查询？

How could I rewrite this LINQ query in a fluent style from sql like style?

c#

linq

service