redirect if drop-down list is empty

 I have a page AddItems.aspx  where items belonging to a category are added to a database.
On page ManageItems.aspx there is a dropdown list DDLItems showing the items that have been added to that category.
PROBLEM:     If a user goes to the ManageItems page, but the dropdown list has no Items in it because he never entered any on the AddItems page, I want to redirect that person to the AddItems page
I am using VB and fiddling around tying to get the code identifying DDLItems as empty that I could put in the page load event of the ManageItems.aspx page that would redirect the user to the AddItems.aspx
What would the code look like, or is there a better approach?
 Thanks

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