How to neatly query corresponding object array ite

Question

I have an array of objects that'll be used for some process.

var x = new List<MyObject>() { new MyObject(), new MyObject(), ... }.ToArray();

After the process, it returns an array of results corresponding to each of the input objects.

var y = MyProcess(x); // returns List<MyResult>

Now, my question is how can I query a list of results with a given condition and the corresponding input objects?

For example, if y[2].IsOkay is false, I want to obtain both x[2] and y[2] in another array. And the objects in array x and y don't have a reference key except the index.

Answer 1

Well, you can use Zip to pair them up:

var pairs = x.Zip(y, (a, b) => new { a, b })
             .Where(pair => !pair.b.IsOkay)
             .ToArray();

You can change the delegate passed to Zip to compose the two values differently if you want - for example, using a named type instead of the anonymous type I've got above.