How does the "for each in" work

array<System::Byte> ^temp_2 = gcnew array<System::Byte>(256);
System::Int32 count_1 = 0;

for each(System::Byte %element in temp_2)
{	
element = System::Byte::Parse(count_1.ToString());
count_1 +=1;
};
for each(System::Byte element in temp_2)
{
System::Console::WriteLine(element.ToString());
}; 
System::Console::ReadLine(); 

(fig. 1)

I don't understand why the identifier has to be a tracking reference to modify the item in the array. As I learnt just `element`, not `%element`, is a pointer to what's the array pointing to. When I try to deference the pointer like below. (fig. 2)

for each(System::Byte element in temp_2) 
{ 
element = System::Byte::Parse("23"); 
};

the elements don't get modified. but when I do: (fig. 3)

for each (System::Byte %element in temp_2) 
{ 
element = System::Byte::Parse("23"); 
};

the elements do get modified. In fig 2. I have deferenced the pointer but the element in the array doesn't get modified. I don't understand why. Can someone please explain this to me.