LEFT OUTER JOIN in LINQ

Question

How to perform left outer join in C# LINQ to objects without using join-on-equals-into clauses? Is there any way to do that with where clause? Corr

Answer 1

Easy way is to use Let keyword. This works for me.

from AItem in Db.A
Let BItem = Db.B.Where(x => x.id == AItem.id ).FirstOrDefault() 
Where SomeCondition
Select new YourViewModel
{
    X1 = AItem.a,
    X2 = AItem.b,
    X3 = BItem.c
}

This is a simulation of Left Join. If each item in B table not match to A item , BItem return null