change rectangleShape with a comboBox C++
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Im working with C++ in VisualStudio 2010. I have a form with a comboBox that has a bunch of different items listed, Box1,Box2,Box3,Box4, ETC... I have a bunch of rectangleShapes that are named Box1,Box2,Box3,Box4, ETC... When I select one of the names in the comboBox I'm trying to make the complementing rectangleShape's fillcolor change from White to Black.

This is my Code under the comboBox1_SelectedIndexChanged event

	String^ x = comboBox1->SelectedItem->ToString();  *// x=name of the rectangleShape*
	x->FillColor = System::Drawing::Color::Black;

but C++ keeps looking at string variable x as a string. Im trying to make the above code work the same as this code,

Box1->FillColor = System::Drawing::Color::Black;

How do I get C++ to see the string that is stored inside of x as the name of the rectangleShape?