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C# Querying With LINQ Query Operators Joins

Ramy Elsaraf
Ramy Elsaraf
7,633 Points

Need assistance

Create a variable named ourBirds and assign to it a LINQ query that is the result of a join from myBirds onto yourBirds using the Name property as the key. Make sure to return the birds that are the same between the two lists

var myBirds = new List<Bird> 
    new Bird { Name = "Cardinal", Color = "Red", Sightings = 3 },
    new Bird { Name =  "Dove", Color = "White", Sightings = 2 },
    new Bird { Name =  "Robin", Color = "Red", Sightings = 5 }

var yourBirds = new List<Bird> 
    new Bird { Name =  "Dove", Color = "White", Sightings = 2 },
    new Bird { Name =  "Robin", Color = "Red", Sightings = 5 },
    new Bird { Name =  "Canary", Color = "Yellow", Sightings = 0 }
var ourBirds = myBirds.Join(yourBirds) b=> b.Name , n=> n,  (bird, name) => bird;

3 Answers

William Li
William Li
Courses Plus Student 26,868 Points

I can see that your solution is almost correct here, 2 small issues though.

  • myBirds.Join(yourBirds), the .Join() parenthesis is closed right after the yourBirds, this is incorrect, it should've spanned all the way to the end of the line.
  • forgot the .Name property for n.
var ourBirds = myBirds.Join(yourBirds, b=> b.Name , n=> n.Name,  (bird, name) => bird);

hope it helps.

var ourBirds = myBirds.Join(yourBirds,
                        myBirds => myBirds.Name , yourBirds => yourBirds.Name,
                       (myBirds, yourBirds) => myBirds);

This ought to be clearer & more self-documenting.

Your solution seems to be clearer, but it won't compile on the challenge. Any ideas why?