从comboBox获取数据并使用它来获取另一个组合框中的数据

Question

I have a two comboboxes in my app. One of them, cmb1 , is binding with a table called Branches, and the other one, cmb2 , is binding with another table called teachers . The relation between them is many to many in a table called subjectteachers . I need to know how to take the Id of selected cmb1 and search in table subjectteachers with that id and get the name from table teachers to put it in cmb2

CollegeContext cd = new CollegeContext();
        Branch SectionCB = CBTypeOfSection.SelectedItem as Branch;

        var query = from b in cd.Branches
                    where (from st in cd.SubjectTeachers
                           where (st.IdBranch == SectionCB.Id &&
                          (from t in cd.Teachers
                           where
                           (t.Id == st.IdTeacher)
                           select t.Name) select st))
                           select b;

        TeachersComboBox.ItemsSource = query.ToList();

Answer 1

this is called lambda its really helpfull hope you like it.

   var query = cd.Subjectteachers.Where(x=>x.IdBranch==SectionCB.Id).Select(x=>x.Teacher);

    TeachersComboBox.DisplayMemberPath = "idwork";