c# - Linq: find elements with common properties but different types -

i have 2 list objects:

class class1 {     public int id { get; set; }     public string name { get; set; }     public guid uniqueidentifier { get; set; }     public bool isvalid { get; set; } }  class class2 {     public int identifier { get; set; }     public string producer{ get; set; }     public guid guid { get; set; }     public int supplierid { get; set; } } 

is there way use linq elements of type class1 list have same id (identifier) , guid elements of type class2 second list?

here 1 way it:

var result = list1     .where(x => list2.any(y => x.id == y.identifier && x.uniqueidentifier == y.guid))     .tolist(); 

please note version not optimized large lists. if lists small, fine. if have large lists, need solution involves things hashsets. here example:

var list2hashset = createhashset(list2.select(x => new {x.identifier, x.guid}));  var result = list1     .where(x => list2hashset.contains(new {identifier = x.id, guid = x.uniqueidentifier}))     .tolist(); 

where createhashset defined this:

public static hashset<t> createhashset<t>(ienumerable<t> collection) {     return new hashset<t>(collection); } 

i had create simple method because compiler complaining cannot resolve correct constructor overload. not sure why.