Remove one Item in ObservableCollection

Question

I have some method like:

public void RemoveItem(ObservableCollection collection, SomeClass instance)
{
    if(collection.Contains(instance))         


        

Answer 1

Your problem is that you are trying to remove an object from the collection that is not in that collection. It might have the same property values, but it is not the same object. There is a simple way around this if your object has a uniquely identifiable property, such as Id:

public void RemoveItem(ObservableCollection collection, SomeClass instance)
{
    collection.Remove(collection.Where(i => i.Id == instance.Id).Single());
}

The idea is that we are getting the actual item from the collection and then passing that into the Remove method.