asp.net mvc - Keep a session variable value after it has been cleared? -

question background:

i have session object used store list of object called 'cartitems'. convert object actual instance, set list variable clear list. sent to viewbag variable , sent view.

the issue:

what i'm trying may not possible clear list instance of cartitems references lost aswell. please see following code:

 public actionresult complete(string orderid)     {         //retrieve cartitem list session object.         list<cartitem> cartitems = (list<cartitem>)session["cart"];          //set list value instance.         list<cartitems>copyofcartitems= cartitems;          //set viewbag properties.         viewbag.orderid = orderid;         viewbag.cartitems = copyofcartitems;          //clear list of cartitems. **issue** occurring.         //once cleared objects have properties set         //this list removed. means viewbag.cartitems property          //is null.         cartitems.clear();          return view(viewbag);     } 

can store value without losing after clearing list?

when

listcopyofcartitems= cartitems;

you creating variable name of copyofcartitems points same object cartitems. in other words cartitems , copyofcartitems 2 names same object.

so when cartitems.clear(); clearing list items on base object.

to around this, make copy of cartitems, rather creating reference

list<cartitems> copyofcartitems = new list<cartitems>();  cartitems.foreach(copyofcartitems.add); //copy cartitems