static void Main(string[] args)
{
var processor = new ImageProcessor();
var filters = new ImageFilters();
Action <Image> imageFilterHandler = filters.ApplyBrightness;
imageFilterHandler += filters.ApplyContrast;
imageFilterHandler += ResizeImage;
processor.Process("C:/Photos/sample.jpg", imageFilterHandler);
}
//Other developers won't be able to apply a filter that hasn't been defined
//To make a new filter, he's going to have to decompile and redeploy the code
//With delegates a developer create his own filter without relying on this code
public void ApplyFiltersWithoutDelegate(string path)
{
var image = Image.Create(path, "img");
var filters = new ImageFilters();
filters.ApplyBrightnessFilter(image);
filters.ApplyContrastFilter(image);
filters.ApplyResizeFilter(image);
image.Save();
}
static void ClientWithDelegate()
{
ImageProcessor imageProcessor = new ImageProcessor();
ImageFilters imageFilters = new ImageFilters();
ImageProcessor.ImageFilterHandler filterHandler = imageFilters.ApplyBrightnessFilter;
//To add another filter
//Those methods must have the same return type as well as the same parameters
filterHandler += imageFilters.ApplyContrastFilter;
//Add created filter
filterHandler += ApplyRedEyeFilter;
imageProcessor.ApplyFiltersWithDelegate(@"C:\img.jpg", filterHandler);
}