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Garbage collector question - regarding combo boxes

Ok, lets say I have a form with a ComboBox. And, let's say I've just created 4 objects. I then write code to add each of these objects to the combo box when a dropdown event is fired. That is, when the user clicks the dropdown portion of the ComboBox to display its contents, I have some code that adds each of my four objects <comboBox.Items.add(object1); comboBox.Items.add(object2), etc...>. Now, lets say I create a button on my form that sets all four of these objects to null and I press this button after displaying the contents of the combo box. My question is, since I already displayed the contents of my combo box (which then created additional references to my 4 objects as it added them to the comboBox) will the GC be able to collect these 4 objects? I suspect not, but I want to be perfectly sure. If the answer is "no", then how to I get fix this situation? (I ask this because my example is a very simple version of a very large project I am working on).

To make sure my point is clear, here is some pseudocode:

Object object1 = new Object();
Object object2 = new Object();
Object object3 = new Object();
Object object4 = new Object();

//event handler for combo box drop-down event
comboBox.Items.add(object1);
comboBox.Items.add(object2);
comboBox.Items.add(object3);
comboBox.Items.add(object4);

//event handler for click event attached to button that nulls all objects
object1 = null;
object2 = null;
object3 = null;
object4 = null;

ASKER CERTIFIED SOLUTION

Thandava Vallepalli

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See answer

rnicholus

ASKER

Actually, I need to insert the actual objects in the comboBox. Otherwise I don't see a way to access the object from the comboBox. My app is setup so the user can select an object from the combobox and display its properties. I'm not aware of a good way to do this other than inserting the object itself into the box. Is there?

However, I figure clearing the comboBox after it goes out of focus may help this problem, since, after clearing the combobox, the references no longer exist. Does this sound like a sold idea?

Razzie_

Like itsvtk said, no, they won't be GC'd.

If you want that to happen, you might try to insert a clone of the object instead of the object itself? Let your object inherit the IClonable interface, call the clone() method and add the cloned object to the combobox. Or, add a Clone() method to your object and return this.MemberWiseClone(). Please note, though, that these are shallow copies and I don't know if that is a problem.

HTH,

Razzie