Question

I have a button that creates a CheckBoxList. The items in the CheckBoxList are selected based on a user’s current notification subscriptions. I’m storing the true or false value of the selected item.

After the users change their subscriptions by checking or unchecking a box in the CheckBoxList, they click another button to update their notification subscriptions. I need to compare the Viewstate["PREV"] with the changed selections on postback and run some functions based on the changes.

ArrayList list = new ArrayList();
for (int i = 0; i < checkBoxList1.Items.Count; i++)
{
    list.Add(checkBoxList1.Items[i].Selected.ToString());
}
ViewState["PREV"] = list;

Even though I can’t see the values with a Response.Write, the values for the ViewState are correct when I add a watch in debug.

The problem I’m having is how to approach the next step to do the comparison. This is what I want to accomplish:

            for (int i = 0; i < checkBoxList1.Items.Count; i++)
        {
            //if checkbox state goes from false to true, subscribe to topic
               //mySubscribeMethod
            //else if checkbox state goes from true to false, unsubscribe to topic
               //myUnsubscribeMethod
            //else if checkbox state is unchanged, do nothing
        }

Answer 1

You can try something like this

ArrayList list =  ViewState["PREV"] as ArrayList;
for (int i = 0; i < checkBoxList1.Items.Count; i++)
{
     if (checkBoxList1.Items[i].Selected == true && Convert.ToBoolean(list[i]) == false)
       {
           // Subscribe Method
       }   
     if (checkBoxList1.Items[i].Selected == false && Convert.ToBoolean(list[i]) == true)       
       {
           // Unsubscribe Method
       }
     else
       {
           // Continue to loop
       } 
}