>It need file name, but I only have image in a general field in my table.
>How can I deal with it?

Then Image Control works "perfectly" with General field. You only need to use Picture property of that control. Keep in mind that if the user who added the picture in General Field used a different application to manage images which is not installed on current user you will be in trouble.
I always try to keep the pictures away from my tables. That cause so many troubles. Better store only path to them. But if you need to keep the pictures in the table I am with Edward here, use BLOB field and use PictureVal property to show that field.