CopyEntity

CopyEntity

CopyEntity is a method, that is available within any entity. In the model of the AI-Framework, the call is: .Copy. This is the functional name. It copies all fields of an entity (which is a record in memory) to a new entity.

Read more about this in How to > Basic concepts > Entities 

Example of usage

public IMethodCall MakeCopyOfOrder()
{
    return Method(() =>
    {
        var currentOrder = OrdersView.CreateItemReference();
        var newOrder = OrdersView.CreateItemReference();

        return new Body
        {
            currentOrder.Assign(OrdersView.Current),
            newOrder.Assign(currentOrder.Copy()),
            newOrder.AssignNextOrderNr(),
            newOrder.OrderDateTime.Assign(DateTimeExpression.Now),
            newOrder.Status.Assign(OrderStatus.Open),
            Orders.Save()
        };
    })
    .SetWorkDescription("make a copy of an order")
    .SetImage(CommonImages.ArrowRight)
    .Call();
}

Explanation of the example

This is a method, named MakeCopyOfOrder(), which is situated inside the Entity OrderEntity. It has therefore direct access to the data, related to the table Order.

• Line 5: OrdersView is a view, based on the OrderEntity. The variable currentOrder is defined as a new instance of a record (in memory).
• Line 6: Another variable, newOrder, is also defined as a new instance of a record (in memory).
• Line 10 assigns the Current record of the OrdersView to the variable currentRecord.
• It all happens in line 11: All data in the record, that was just assigned to the variable currentOrder, is now copied to the variable newOrder – that is: the new record in memory.
• After that, three values (fields) are overwritten with new values, so the new record will be unique:
  • A new Order number (line 12),
  • an order date and time stamp (line 13) and
  • the status is set on Open.
• In line 15, the changes that were made in Orders – in memory, that is on entity level – will now be written to the database with Orders.Save().

How to use this

Anywhere in the model code, where the OrderEntity is available, a button can be placed on a form, that invokes this method: Orders.MakeCopyOfOrder(). If, for example, the form shows a list of orders, clicking the button will make a copy of the order that is currently selected in that list.

Article ID: 359
Created: Tue, Jan 28, 2020
Last Updated: Tue, Jan 28, 2020

Online URL: https://wiki-ai-framework.abstract-it.nl/article/copyentity-359.html