Is there any simple way to check any class instance for modifications?

Question

Let's say i have a class like that:

class Test
{
   string asd;
   int dsa;
}

Later, I create instance of this class, then later it may change values for data members.
I need a simple compare method without comparing all class members.
Something like that:

Test t = new Test();
t.asd = "asd";

SOMETHING SMTH = GetSOMETHINGof(t);

a.dsa = 3;

if (GetSOMETHINGof(t) != SMTH)
   //object modified

Maybe someone know built-in things that can be used for that? I know i can implement Equal and etc, but that's not what i want. There is too much classes and a lot of members.
I use C# and .net 4.0

could you use private variables, public properties and implement the propertychanged event on those properties? that way you can subscribe to the event and have it fire when something changes — wterbeek, Sep 14 '12 at 06:10
Maybe this can help you : http://stackoverflow.com/questions/2363801/what-would-be-the-best-way-to-implement-change-tracking-on-an-object — David, Sep 14 '12 at 06:10
there is a lot of changes in source code if switch to properties. I can't pass properties as ref, out and etc. I need something more cool :D — Kosmo零, Sep 14 '12 at 06:15
or this http://stackoverflow.com/questions/9624318/how-to-implement-a-simple-generic-comparison-in-c-sharp — ravi, Sep 14 '12 at 06:17
This will be helpful http://stackoverflow.com/questions/2502395/comparing-object-properties-using-reflection — Prasanna, Sep 14 '12 at 06:18
i found an interesting way here: http://stackoverflow.com/questions/2502395/comparing-object-properties-using-reflection by Oskar Kjellin. I just hope base types as int and etc don't have properties :D since i going o modify it for recursive object properties comparing. Thanks to everyone! — Kosmo零, Sep 14 '12 at 06:32
err, also hope it works for private and protected members too... but would be weird if i can that easy access private member just by calling GetProperties() — Kosmo零, Sep 14 '12 at 06:45

score 1 · Accepted Answer · edited May 23 '17 at 12:27

1

Compare .NET Objects 1.4.2.0 by Greg Finzer http://www.nuget.org/packages/CompareNETObjects

edited May 23 '17 at 12:27

Community

1
1

answered Sep 14 '12 at 06:29

Prasanna

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score 1 · Answer 2 · answered Sep 14 '12 at 06:38

Add extra property to keep state of the object:

public class A
{
    public bool HasChanged { get; set; }

    object _Value;
    public object Value
    {
        get
        {
            return _Value;
        }
        set
        {
            HasChanged = value != _Value;
            _Value = value;
        }
    }

    public A(object _value)
    {
        _Value = _value;
        HasChanged = false;
    }
}

and use it:

        A a = new A(5);
        Console.WriteLine(a.HasChanged);  //false
        a.Value = 6;
        Console.WriteLine(a.HasChanged);  //true
        a.HasChanged = false;
        Console.WriteLine(a.HasChanged);  //false

Is there any simple way to check any class instance for modifications?

2 Answers2