Create Rollover Graphics in ASPX Pages

Create a Hyperlink control on the .aspx page (with an ID of 'lnkImage' in this example). In the codebehind, create a new image, set it's attributes and add it to the controls collection of the hyperlink (substitute you own images for icon.gif and icon_hot.gif):

Private Sub Page_Load ...
    Dim IMG as new WebControls.Image
    IMG.ImageUrl = "Images/icon.gif"
    IMG.Attributes.Add("onmouseover", "this.src='Images/image_hot.gif';")
    IMG.Attributes.Add("onmouseout", "this.src='Images/image.gif';")
    IMG.Controls.Add(IMG)
End Sub