Problem merging IEnumerable<T> using Lambda expressions

I have 2 IEnumerables which are of type 'Product' - totalProducts and ProductsChosen. As the names suggest totalProducts holds all the products available and ProductsChosen holds the products chosen by the user .

The Product class has properties Id ,number, and IEnumerable<AdditonalOptions> options.

I am trying to merge these 2 IEnumerables like this

public IEnumerable<Product> MergeProducts(IEnumerable<Product> Products, IEnumerable<Product> ProductsChosen)
{
    return ProductsChosen.Concat(Products.Where(r => !ProductsChosen.Any(x => x.ProductId.Equals(r.ProductId))));
}

I have used the code to merge from here

This code wor开发者_StackOverflowks fine only if I consider the product ids but I would also like to merge the IEnumerable<AdditionalOption> options of the productsChosen with that of the totalProducts if the Product Ids are same.But I am not sure how to do that.

Could someone please help me with that?

Thanks

As the chosen products have different options that the total products they must be distinct instances. Since you have said that total products are all that are available then I assume that the set of chosen product ids must be a subset of the product ids.

Also, since the chosen products are distinct instances then it is possible that there may be zero or more chosen products per each total product so my solution works for this case too. It will equally work if there are only zero or one.

Further, since they are distinct instances and the options property is an IEnumerable it made sense to me to create a new set of instances for the merged products so as to not alter the original set of total products.

public IEnumerable<Product> MergeProducts(
    IEnumerable<Product> Products,
    IEnumerable<Product> ProductsChosen)
{
    return
        from p in Products
        join pc in ProductsChosen on p.Id equals pc.Id into pcs
        select new Product()
        {
            Id = p.Id,
            number = p.number,
            options = p.options
                .Concat(
                    from pc2 in pcs
                    from ao in pc2.options
                    select ao).ToArray(),
        };
}

You didn't explain what number property is, so I've just done a simple assignment for this value from the Products list and ignored this value from the ProductsChosen list.

Also, you didn't say how the AdditionalOptions needed to be merged. This is no Merge method for enumerables. You need to use something like Concat or Union to do a merge. I've chosen Concat but that easy to change.

Does this work for you?