Add examples of AddWatermarkingHandler

Author: lilith

Diff for: README.md

@@ -175,19 +175,26 @@ namespace Imageflow.Server.Example
                 // Register a named watermark that floats 10% from the bottom-right corner of the image
                 // With 70% opacity and some sharpness applied. 
                 .AddWatermark(
-                    new NamedWatermark("imazen", 
+                    new NamedWatermark("imazen",
                         "/images/imazen_400.png",
                         new WatermarkOptions()
                             .SetFitBoxLayout(
-                                new WatermarkFitBox(WatermarkAlign.Image, 10,10,90,90), 
-                                WatermarkConstraintMode.Within, 
-                                new ConstraintGravity(100,100) )
+                                new WatermarkFitBox(WatermarkAlign.Image, 10, 10, 90, 90),
+                                WatermarkConstraintMode.Within,
+                                new ConstraintGravity(100, 100))
                             .SetOpacity(0.7f)
                             .SetHints(
                                 new ResampleHints()
                                     .SetResampleFilters(InterpolationFilter.Robidoux_Sharp, null)
                                     .SetSharpen(7, SharpenWhen.Downscaling))
-                            .SetMinCanvasSize(300,300))));
+                            .SetMinCanvasSize(200, 150)))
+                .AddWatermarkingHandler("/", args =>
+                {
+                    if (args.Query.TryGetValue("water", out var value) && value == "mark")
+                    {
+                        args.AppliedWatermarks.Add(new NamedWatermark(null, "/images/imazen_400.png", new WatermarkOptions()));
+                    }
+                }));
 
 
             app.UseStaticFiles();

Diff for: examples/Imageflow.Server.Example/Startup.cs

@@ -136,7 +136,14 @@ public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
                                 new ResampleHints()
                                     .SetResampleFilters(InterpolationFilter.Robidoux_Sharp, null)
                                     .SetSharpen(7, SharpenWhen.Downscaling))
-                            .SetMinCanvasSize(200, 150))));
+                            .SetMinCanvasSize(200, 150)))
+                .AddWatermarkingHandler("/", args =>
+                {
+                    if (args.Query.TryGetValue("water", out var value) && value == "mark")
+                    {
+                        args.AppliedWatermarks.Add(new NamedWatermark(null, "/images/imazen_400.png", new WatermarkOptions()));
+                    }
+                }));