How to rotate an Image in C#?

public static Image RotateImage(Image img, float rotationAngle)
{
    //create an empty Bitmap image
    Bitmap bmp = new Bitmap(img.Width, img.Height);
    //turn the Bitmap into a Graphics object
    Graphics gfx = Graphics.FromImage(bmp);
    //now we set the rotation point to the center of our image
    gfx.TranslateTransform((float)bmp.Width / 2, (float)bmp.Height / 2);
    //now rotate the image
    gfx.RotateTransform(rotationAngle);
    gfx.TranslateTransform(-(float)bmp.Width / 2, -(float)bmp.Height / 2);
    //set the InterpolationMode to HighQualityBicubic so to ensure a high
    //quality image once it is transformed to the specified size
    gfx.InterpolationMode = InterpolationMode.HighQualityBicubic;
    //now draw our new image onto the graphics object
    gfx.DrawImage(img, new Point(0, 0));
    //dispose of our Graphics object
    gfx.Dispose();
    //return the image
    return bmp;
}

Rotate and Flip an Image