User-1221966532 posted
hi alisakhi,
thanks for your reply, which gave me the lead. It certainly was not complete, but was the information I was after and with a short google-ing found the right form of the Editor attribute.
I used the complete
[System.ComponentModel.Editor(typeof(System.Web.UI.Design.UrlEditor), typeof(System.Drawing.Design.UITypeEditor))]
public string ImageURL
{
get{...}
set{...}
}
version which is the file browsing editor usually seen in asp control properties.