Selecting on a many table using Linq
I have a recipe table that has a related ingredients table on one to many basis.
How do I select using Linq ingredients that have a ingredientName column and it should contain a specified word.
This is what I tried.
IQueryable<OurRecipes.Domain.Linq2Sql.Recipe> recipes = _dbctx.Recipes.AsQueryable();
foreach (string word in searchdata.Keywords)
{
recipes = recipes.Where(r => r.RecipeTitle.Contains(word));
recipes = recipes.Where(r => r.Ingredients.Where(i => i.IngredientName.Contains(word)));
}
I get cannot convert type 'etc' to bool error.
Any ide开发者_运维问答as Malcolm
The error lies here:
recipes = recipes.Where(r => r.Ingredients.Where(i => i.IngredientName.Contains(word)));
The condition inside Where
must return a boolean, in this case, the r.Ingredients.Where(i => i.IngredientName.Contains(word))
will not return a boolean, and hence the error.
This is how you can fix the problem:
recipes = recipes.Where(i => i.Ingredients.Any(row=>row.IngredientName.Contains(word)));
r.Ingredients.Where(i => i.IngredientName.Contains(word)));
replace with
r.Ingredients.Any(i => i.IngredientName.Contains(word)));
Btw, I like SQL like syntax more as it more netural. The same:
from r in _dbctx.Recipes
where r.Ingredients.Any(i => i.IngredientName.Contains(word)));
select r;
This will select all recipies that has ingredients with name contains word.
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