Creat a copy

[xSwan]

I have this example:

class testclass
{
	public int i;
	public testclass(int i)
	{
	this.i = i;
	}
}

class Class1
{		[sTAThread]
	static void Main(string[] args)
	{
		testclass test1 = new testclass(0);
		testfunction(test1);
		Console.Write(test1.i);
		Console.Read();


	}
	static void testfunction(testclass test2)
	{
		testclass test3 = test2;
		test3.i++;
	}
}

 

What can i do if i dont want test1 to be 1 then I call the testfunction?

 

Sorry for the variable but I'm not good for find names for varibles, :D

[Nerseus]

If you're asking why the testfunction, which assigns test3 to test2 also increments the private variable i inside of class2, it's because the contents of a class are not copied even when a function is declared as by val (meaning you did NOT use ref or out).

 

To have testfunction work on a copy of the test class passed in, you'd have to perform a shallow copy and work with that. You could also define the testclass Class to be a struct. The contents of a struct is passed by value so incrementing a member variable would affect the copy, not the original.

 

Otherwise, things are working as expected - at least they are to me. It's a matter of realizing what's working so you know what to expect then coding with that knowledge in mind.

 

-Nerseus

[xSwan]

Yah, I'm understand what it do then I see it do it, but my question is, how can I copy the test2 into test3 and do what I want to with the test3, without the test1 be chance to?

 

And I cant just made it to a struct becurse realy its other class, I take from a Direct3.

 

So my real question is, how can I copy a class and not only its ref.?

[Heiko]

Some classes implement .clone methods.

 

For your own classes, you have to implement your own clone method.

[xSwan]

Yeah, I could add a methods, but isn't there an other way?

[JABE]

How about this?

 

static void testfunction(testclass test2) {

testclass test3 = new testclass(test2.i);

test3.i++;

}

 

Otherwise, you really have to implement ICloneable.

[xSwan]

Nope, it can't do it, too :(

Bcurse it, the testclass, just is a test of how it work, not the real object. So I must try to find an other way to sovle my problem :(