c# - Duplicate Object and working with Duplicate without changing Original

Question

Assuming I have an Object ItemVO in which there a bunch of properties already assigned. eg:

ItemVO originalItemVO = new ItemVO();
originalItemVO.ItemId = 1;
originalItemVO.ItemCategory = "ORIGINAL";

I would like to create another duplicate by using :

duplicateItemVO = originalItemVO;

and then use the duplicateItemVO and alter its' properties, WITHOUT changing the originalItemVO:

// This also change the originalItemVO.ItemCategory which I do not want.
duplicateItemVO.ItemCategory = "DUPLICATE" 

How can I achieve this, without changing the class ItemVO ?

Thanks

public class ItemVO     
{
    public ItemVO()
    {
        ItemId = "";
        ItemCategory = "";
    }

    public string ItemId { get; set; }
    public string ItemCategory { get; set; }
}

question from:https://stackoverflow.com/questions/9233046/duplicate-object-and-working-with-duplicate-without-changing-original

Answer 1

You would need to construct a new instance of your class, not just assign the variable:

duplicateItemVO = new ItemVO 
    { 
        ItemId = originalItemVO.ItemId, 
        ItemCategory = originalItemVO.ItemCategory 
    };

When you're dealing with reference types (any class), just assigning a variable is creating a copy of the reference to the original object. As such, setting property values within that object will change the original as well. In order to prevent this, you need to actually construct a new object instance.