c# - Groupby list within the list using LINQ -

i have 2 classes:

class customer {     public string name { get; set; }     public string zipcode { get; set; }     public list<order> orderlist { get; set; } }  class order {     public string ordernumber { get; set; } } 

using linq, want list of orders group zipcode. if zipcode "12121" has 10 customers , each has 2 orders should return me 1 zipcode list of 20 orders.

i trying not able figure out whats wrong

var orders = br.custorderlist .select(r => new {     r.zipcode,     r.name,     r.orderlist }) .groupby(x => new { x.zipcode, x.orderlist});  

any please?

this should want:

var orders = br.custorderlist     .groupby(x => x.zipcode)     .select(g => new     {         zipcode = g.key,         orders = g.selectmany(x => x.orderlist)     });