Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/ModelBinding/ComplexModelBinder.cs

@@ -0,0 +1,31 @@
+namespace System.Web.ModelBinding {
+
+    public sealed class ComplexModelBinder : IModelBinder {
+
+        public bool BindModel(ModelBindingExecutionContext modelBindingExecutionContext, ModelBindingContext bindingContext) {
+            ModelBinderUtil.ValidateBindingContext(bindingContext, typeof(ComplexModel), false /* allowNullModel */);
+
+            ComplexModel complexModel = (ComplexModel)bindingContext.Model;
+            foreach (ModelMetadata propertyMetadata in complexModel.PropertyMetadata) {
+                ModelBindingContext propertyBindingContext = new ModelBindingContext(bindingContext) {
+                    ModelMetadata = propertyMetadata,
+                    ModelName = ModelBinderUtil.CreatePropertyModelName(bindingContext.ModelName, propertyMetadata.PropertyName)
+                };
+
+                // bind and propagate the values
+                IModelBinder propertyBinder = bindingContext.ModelBinderProviders.GetBinder(modelBindingExecutionContext, propertyBindingContext);
+                if (propertyBinder != null) {
+                    if (propertyBinder.BindModel(modelBindingExecutionContext, propertyBindingContext)) {
+                        complexModel.Results[propertyMetadata] = new ComplexModelResult(propertyBindingContext.Model, propertyBindingContext.ValidationNode);
+                    }
+                    else {
+                        complexModel.Results[propertyMetadata] = null;
+                    }
+                }
+            }
+
+            return true;
+        }
+
+    }
+}