c# - Advanced Search using Lambda Expression -

i want implement advanced search in asp.net mvc application, user can select 1 or more criteria product search.

let's have these criterias: color, size, price range.

this far till now

productsizelist = db.productsizes.where(productsize =>     (string.isnullorempty(productcolorid) || productsize.product.productcolors.where(a => a.colorid == intcolorid).any())     ).groupby(x => x.productid).select(grouped => grouped.firstordefault()).tolist(); 

i have many-to-many relationship between product , color tables, , productcolor 1 linking them. same thing product, productsize, size tables.

the code working size, , price range. problem color, because .any() returns when finds first product. if there more 1 product, returns first one.

so, want know if there method, or way able products specified color.

i searched lot, , know can build clause dynamically, think work requirements. if there simple fix more happy.

edit

i removed working-as-wanted code suggested @jeroen, , left 1 want fix.

solved

i fixed it, combining @jason , @marlon answers. i'll put solution in separate answer. want understand 2 points:

• why worked correctly when based query on product?
• why `.distinct()` didn't thing, , got duplicated products.

please try this. uses iqueryable let more construct conditions before executing against database when tolist called.

var query = db.productsizes.asqueryable(); if (string.isnullorempty(productcolorid) == false)     query = query.where(productsize => productsize.product.productcolors.any(a => a.colorid == intcolorid)) if (string.isnullorempty(sizeid) == false)     query = query.where(productsize => productsize.size.id == intsizeid); if (string.isnullorempty(from) == false)     query = query.where(productsize => productsize.price >= decimalfrom); if (string.isnullorempty(to) == false)     query = query.where(productsize => productsize.price <= decimalto); var productsizelist = query     .select(productsize => productsize.productid)     .distinct()     .tolist();