LINQ and optional parameters
The parameters of the method could accept null values and the Where restriction could be evaluated for each not null parameter:
IQueryable<Product> q = databaseObject.Products;if (catId != null){ q = q.Where(p => p.Category == catId);}if (brandId != null){ q = q.Where(p => p.Brand == brandId);}// etc. the other parametersvar result = q.ToList();
If this is Linq To SQL:
databaseObject.Products.Where(p=> (catId == null || p.Category == catId) );Linq To SQL, efficiently writes the SQL sent to backend without a where clause if CatId is null. You can have multiple of these constructs, and only those with a nonNull value is included in the where construct.
databaseObject.Products.Where(p=> ((catId==null) || (p.Category == catId)))For your other 3 optional parameters, you can AND them in, doing your entire search in one linq statement.