Hyperlink code

I have a hyperlink which calls itself carrying a parameter :

<a href="admin_page.asp?delfolder=<%=rsFolders.Fields.Item("DIR_NAME").Value%>">del</a>

The asp script holds the name of a folder which is to be deleted.

What I want to do is when the user clicks on the hyperlink, promt them "Do you want to do this ?". If they dont then I wont reload the page else I will.

How do I go about this ?
Is it possible ?

Thanks in Advance

Would you want this done in ASP too?

to someone who would know. If I used the onClick event with JavaScript, would both events fire?