Question

I need to execute functionality whereby if the user is going to close the window (or perform some other action) without saving their changes, they are going to be informed with a message box.

In order to be able to do this, I need to be able to know whether changes have been made to the object in question since the window was opened.

I’m thinking a way to do this is to create a copy of the object when the window loads and keep it as _original and then before the window closes I can compare it against the object that may or may not have been changed.

What is the best way to copy the object into _original, without both of them simply having a reference to the same place in memory?

Also, what is the best way to compare the two objects after, to see if the object is different than _original?

Answer 1

You could implement your object in a way where it maintains a modified state e.g.

public class StatefulObject
{
    private string _propertyOne;

    public StatefulObject()
    {
        this.Modified = false;
    }

    public string PropertyOne
    {
        get { return this._propertyOne; }
        set
        {
            if (this._propertyOne != value)
            {
                this._propertyOne = value;
                this.Modified = true;
            }
        }
    }

    public bool Modified { get; private set; }
}

This would need some extra work like determining when your just initializing the object (unless you restrict it to the constructor only), however, you get the idea.