应该如何正确使用RegisterForEventValidation

I recently started using ScriptManager. I have an ASP.NET DropDownList control that I'm populating via JavaScript. However, I'm using Event Validation. So I run into the error below if I don't use the "RegisterForEventValidation" call here for my dropdown. How do I know what value(s) to set in the second argument (where I have "value")? I am populating my dropdown via JavaScript, so I won't know what values are there from my code behind. I'm guessing that Render is called during an AJAX partial rendering postback, correct? Or is it not, so this is called regardless of whether I'm doing a full page postback or not. I guess I'm wanting to hear not only the answer to my question, but if you can share your experiences with me about the error below. I love input, just like Johnny #5.I recently started using ScriptManager. I have