Cairo.NativeMethods.cairo_image_surface_create_from_png C# (CSharp) Метод

        internal static extern IntPtr cairo_image_surface_create_from_png(string filename);

 public ImageSurface(string filename)
 {
     surface = NativeMethods.cairo_image_surface_create_from_png(filename);
     lock (surfaces.SyncRoot){
         surfaces [surface] = this;
     }
 }