converting/ saving int

I have a quick question..
I am going off of an example which resembles my project.
I have a a method which updates a control. And one that deletes data.
In the example I am going off of they use an ID as a nvarchar, and My ID is an int.
In there delete method they use:
{
     string id = Request.QueryString["id"]; <------
     dbDeleteEvent(id);
}
 
Since my ID is an int, how can I use there same reasoning but have it as an int?
I tried:
 int ID = Convert.ToInt32(Request.QueryString["ID"]);
and
int ID = int.Parse(Request.QueryString["ID"]);
Any help would be appreciated!
Thanks
 
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