linq - 哪个查询表达式相当于以下 LINQ 查询？

Question

Possible Duplicate:
Can these two LINQ queries be used interchangeably?

var query =  from c_1 in collection_1
             select c_1.collection_2 into c_2
             select c_2.collection_3 into c_3
             select c_3;

相当于

  var query = collection_1
            .Select(c_1 => c_1.collection_2)
            .Select(c_2 => c_2.collection_3)
            .Select(c_3 => c_3);

a) 但是哪个查询表达式等效于以下 LINQ 查询:

var query = collection_1
            .Select(c_1 => c_1.collection_2
            .Select(c_2 => c_2.collection_3.Select(c_3 => new { c_1, c_2, c_3 } )));

谢谢

Answer 1

var query = from c_1 in collection_1
            select from c_2 in c_1.collection_2
                   select from c_3 in c_2.collection_3
                          select  new { c_1, c_2 c_3 };