Question

I want to encapsulate the following query into a method that returns a query result (i.e. members).

I then want to take another query that will query off of that returned result.

---

I learned that I cannot use var as a parameter type or result type within the method that I want to create. I really wanted to have this support to make my life simple.

Additional details:
MembersItemsControl.Items property has a private member ‘_ItemsSourceAsList’ that is of type ‘Users’ which is a class that inherits from an ObservableCollection.

---

Any suggestions?

---

The query code is below:

---

var members = (from member in MembersItemsControl.Items
               where
               (
                   // Match either male or female selection
                   (member as UserInformation).sex.Equals("Male") == 
                       SeekingMale.IsChecked.Value &&
                   (member as UserInformation).sex.Equals("Female") == 
                       SeekingFemale.IsChecked.Value
               )
               ||
               (
                    // Provide both male and female if both options are selected
                    SeekingMale.IsChecked.Value == true &&
                    SeekingFemale.IsChecked.Value == true
               )
               select member);

Answer 1

You can always pass LINQ collection as IEnumerable<Member>.

public IEnumarable<Member> Foo()
{
    var members = (from member in MembersItemsControl.Items
                   where
                   (
                       // Match either male or female selection
                       (member as UserInformation).sex.Equals("Male") == 
                           SeekingMale.IsChecked.Value &&
                       (member as UserInformation).sex.Equals("Female") == 
                           SeekingFemale.IsChecked.Value
                   )
                   ||
                   (
                        // Provide both male and female if both options are selected
                        SeekingMale.IsChecked.Value == true &&
                        SeekingFemale.IsChecked.Value == true
                   )
                   select member);

    return members;
}

Where Member is type of items in MembersItemsControl.Items.