<dxe:ImageEdit Source="/Gemr;component/Images/FakeUI/MedicalRecordFake.jpg"

                       Stretch="Fill"

            ></dxe:ImageEdit>

绝对路径：

img.Source=new BitmapImage(new Uri(@"d:\photo\backgrpunds\arch.jpb"));

相对路径：

img.Source=new BitmapImage(new Uri("images/winter.jpg", UriKind.Relative));