How to store Multiple CheckboxLists in Array ?

<asp:CheckBoxList runat="server" ID="YrChkBox" CssClass="question-wrapper" RepeatLayout="UnorderedList">

                    <asp:ListItem Value="1">SkyDrive</asp:ListItem>
                    <asp:ListItem Value="2">Google Drive</asp:ListItem>
                    <asp:ListItem Value="3">Own FTP server</asp:ListItem>
                    <asp:ListItem Value="4">Database (fx MongoDB)</asp:ListItem>
                    <asp:ListItem Value="5">Local on pc/mac</asp:ListItem>

                </asp:CheckBoxList>

// Create the list to store.
       List<String> YrStrList = new List<string>();
       // Loop through each item.
       foreach (ListItem item in YrChkBox.Items)
       {
           if (item.Selected)
           {
               // If the item is selected, add the value to the list.
               YrStrList.Add(item.Value);
           }
           else
           {
               // Item is not selected, do something else.
           }
       }