Hi,
Base on your description, you want to change the banner that is on the master page according to the current page file, right?
You can try to use this code Request.RawUrl(); in the master page codebehind to get the file name of the current page, then change the banner.
Or you can change the banner in every content page:
For example:
Image image= (Image)this.Master.FindControl("ctl00$Image");
Image.ImageURL = "~/image/001.jpg";
Hope it helps.
Please remember to mark the replies as answers if they help and unmark them if they provide no help.
Yours sincerely,
Amanda Wang
Microsoft Online Community Support