Set image source from code

Hey,

i want to change the source of an image from the code. The images are located on C. Somehow, it doesn't work.

BitmapImage bmpImg = new BitmapImage();
Uri uri = new Uri(file://C:/test.jpeg);
bmpImg.UriSource = uri;
myImage.Stretch = Stretch.Fill;
myImage.Source = bmpImg;

Can anyone please help me.
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