c# - Can two Lists be joined if types are different like List<T> and List<G>? -

i have 2 different classes below:

public class productdto : idto     {         public int parentproductid { get; set; }         public string parentproductnumber { get; set; }         public int supplierid { get; set; }         //more properties     }      public class orderitemsdto : idto     {         public int poid { get; set; }         public system.datetime createddate { get; set; }         public int parentproductid { get; set; }         public int variationid { get; set; }         public system.datetime deliverydate { get; set; }         //more properties     } 

what need join list<orderitemsdto> , list<productdto> on parentproductid (like if database tables) , produce list.

i have tried using union below:

list<productdto> productparents = productmanager.getlist(); list<orderitemsdto> orderitemslist = ordermanager.getlist(); gvpurchaseorderitems.datasource =  orderitemslist.select(o => o.parentproductid).union(productparents.select(pp => pp.parentproductid)); 

but gives me result of list<int> parentproductids found in both of lists need has properties ( columns in above case ) both classes. , couldn't find how select multiple properties select extension method ( kind of beginner )

i know can create new class , map properties manually, curious how lambda expressions or linq. possible, appreciate if point me direction. thanks.

you can use select create anonymous type query:

orderitemslist.select(o => new { o.parentproductid, o.variationid, /* etc */ }) 

so, in case:

gvpurchaseorderitems.datasource =  orderitemslist     .select(o => new { o.parentproductid, o.variationid, /* etc */ })     .union(productparents         .select(pp => new { pp.parentproductid, pp.variationid, /* etc */ }));