How to use projection in linq in such nested scenerio?

Question

I am new to Linq and I just started to study Linq query. I believe this is something to do with projection. But I am clueless how to dig into it to get what I desired in my result. This is my Scenario : Office which has two branches

branch_1, branch_2

branch_1 has dept_1_1 and dept_1_2

branch_2 has dept_2_1 and dept_2_2

each deprtment has employees.

But I need to query through Office to find name of all the employees in dept_2_2 and dept_2_2 is in branch_2

This is something I did.

var result = office.Branch.First()

But first() will give me branch_1 which I do not want how do I get branch_2 and then further dept_2_2 and then all the employees .

I would be thankful to help me out to write linq queries.

Would you please provide us your code and if possible some sample data so we can see where the problem is? — Marco, Feb 22 '16 at 08:23
look at this : http://stackoverflow.com/questions/20974248/recursive-hierarchy-recursive-query-using-linq — Jurion, Feb 22 '16 at 08:23

hari6 · Answer 1 · 2016-02-23T02:56:09.577

0

  var result = from branch in office.Branches
               where branch.Name == "branch2"
               from dept in branch.Departments
               where dept.Name == "dept2"
               select dept.Employees.ToList();

This gives IEnumerable list of all the employees in the branch2 -> dept2

edited Feb 23 '16 at 02:56

answered Feb 22 '16 at 08:37

hari6

14
2

I have just started to learn Linq to object. So I am trying to query in in memory collection of object. I have an Office class which has List, Branch has List and dept has List and Employee has name property. – Nepsydaz Feb 22 '16 at 08:53
@gaurav updated my answer according to your comment. – hari6 Feb 23 '16 at 02:56

score 0 · Accepted Answer · answered Feb 22 '16 at 09:19

I think type of office List<Branch> . Please try this. I hope this helps to you:

        List<Employee>listOfEmployee = office.Where(l =>l.Branch == branch_2 
                                                          &&l.Branch.DeptName == dept_2_2 )
                                                          .Select(l => l.Branch.Dept.Employee.EmpName)
                                                          .ToList();

How to use projection in linq in such nested scenerio?

2 Answers2