I am new to MVC3. In asp.net user control, its fairly easy to create a user control that has a combo box with a button, with hover over event, and a collection property of combo box that then displays a list
how do i achieve this user control (partial view) in mvc3?
What you are looking for is helper methods. You can see a good explanation of it here. In that post, there is a great link for how to do this: Creating Custom HTML Helpers.
I am also a WebForms developer originally, and I had a hard time making the connection between user controls and HTML Helpers. This should give you enough guidance to get started with what you want.