Very often there is a need to add items in a collection of items. Usually we have some object that holds a list of complex objects, for example, one Order contains several OrderItems which are complex objects (has their properties). When creating a Controller and View for such object, Razor ignores these properties and doesn't create input fields for them. In this example, I can show you how I solve this problem without refreshing the page.
One of the first thins that you should do is to create an Editor for the Objects that are in the list, in this example the order items. This editor is simple copy-paste from its Edit.cshtml file, but remember to remove the